Ok, so I got really bored at work the other day, and thought to myself: "How interesting would it be if there was no World Cup qualifiers, and it was just straight knockout, home and away ties all the way until the grand final?"

So, thanks to FIFA World Cup 2014 (a little bit outdated, but I'll probably do it again when the 2018 World Cup game comes out next year), I can make this happen. Here are the draw rules:

Because I'm using FIFA WC 2014 game, that means of the current 211 FIFA members, there are only 203 nations present (Kosovo and Gibraltar hadn't joined FIFA yet, and Bhutan, Brunei, Guam, Mauritania, Mauritius and South Sudan didn't enter).
Even though I'm using FIFA WC 2014, I will be using the CURRENT FIFA Rankings for the seedlings. Seedlings are only used for the first two rounds as follows:
Byes are only to the 2nd round. This is to make a clean 128 nations remaining. Therefore, the top 53 nations, all get a bye through to the second round. (Unfortunately, Australia is 54, so.. we are in the first round.)
Other than that, anyone can be drawn with anyone. The team drawn first is the Home nation for the second leg.
Winner on Aggregate advances. Extra Time and penalties if needed in the second leg. Away goals rule does not affect Extra Time.
This will continue until the FIFA World Cup Final (currently scheduled to be held over 2 legs. This might change to an NPL style of who will host the single leg final)
Because I don't have 203 ping pong balls / tiny pieces of paper, I have used a number generator to determine the draw for the first round. This is so I did not see countries until I typed them in after generating the list of rankings. I will post the first round when I have typed it all out, because at the moment I only have the ranking numbers.

Away First   M1   M2   Home First
Timor-Leste         Afghanistan
Kuwait         Vietnam
Zimbabwe         Turkmenistan
Benin         Guinea-Bissau
Montenegro         Burundi
Equatorial Guinea         Thailand
Slovenia         Trinidad and Tobago
Malaysia         Guinea
Albania         Palestine
Georgia         Niger
Mongolia         Sierra Leone
Rwanda         Papua New Guinea
South Africa         St. Vincent and the Grenadines
Togo         Tahiti
Macau         Andorra
Cayman Islands         Philippines
Mali         Hong Kong
Dominica         Liberia
Tanzania         Gambia
Moldova         Swaziland
Zambia         Dominican Republic
Indonesia         Honduras
Macedonia          Guyana
Seychelles         Nepal
Kazakhstan         Faroe Islands
Cyprus         Aruba
Bolivia         Bahamas
China         Luxembourg
Oman         Namibia
Australia         Suriname
Jamaica         Congo
Central African Republic         India
Gabon         Yemen
Cambodia         Jordan
Cook Islands         Mozambique
Comoros         Canada
Bangladesh         Samoa
Armenia         Lebanon
Sri Lanka         Antigua and Barbuda
St. Kitts and Nevis         British Virgin Islands
Montserrat         U.S. Virgin Islands
Curacao         Anguilla
Laos         Syria
Ethiopia         Djibouti
New Zealand         Saudi Arabia
Guatemala         Barbados
Tajikistan         Chad
Belize         Norway
Lesotho         Maldives
Pakistan         Nicaragua
Cuba         Haiti
Angola         Tonga
Botswana         Finland
St. Lucia         Eritrea
San Marino         Russia
Somalia         Turks and Caicos Islands
North Korea         Libya
Azerbaijan         Solomon Islands
Singapore         Chinese Taipei
Fiji         Kenya
Madagascar         United Arab Emiates
Estonia         Malta
Belarus         Bahrain
Bulgaria         Malawi
Vanuatu         Myanmar
Iraq         Sudan
Kyrgyzstan          Liechtenstein
Latvia         Israel
Granada         American Samoa
Scotland         Sao Tome e Principe
Qatar         Venezuela
Cape Verde Islands         Uzbekistan
Uganda         New Caledonia
Bermuda         Puerto Rico
Lithuania         El Salvador
BYE         Argentina
BYE         Brazil
BYE         Germany
BYE         Chile
BYE         Belgium
BYE         France
BYE         Colombia
BYE         Portugal
BYE         Uruguay
BYE         Spain
BYE         Switzerland
BYE         Wales
BYE         England
BYE         Poland
BYE         Italy
BYE         Croatia
BYE         Mexico
BYE         Peru
BYE         Costa Rica
BYE         Iceland
BYE         Netherlands
BYE         Ecuador
BYE         Egypt
BYE         Turkey
BYE         Ireland
BYE         Slovakia
BYE         Hungary
BYE         Bosnia and Herzegovina
BYE         United States of America
BYE         Ukraine
BYE         Senegal
BYE         Iran
BYE         Cameroon
BYE         Austria
BYE         Northern Ireland
BYE         Tunisia
BYE         DR Congo
BYE         Burkina Faso
BYE         Korea Republic
BYE         Romania
BYE         Nigeria
BYE         Paraguay
BYE         Greece
BYE         Sweden
BYE         Ghana
BYE         Czechia
BYE         Cote D'Ivoire
BYE         Morocco
BYE         Denmark
BYE         Algeria
BYE         Serbia
BYE         Japan
BYE         Panama

P.S. The way I'm doing this, is I play as the home nation for each leg

Great minds think alike.

I might re-do a draw for shits and gigs (but not leave myself limited to World Cup 2014 game ha).

I did one recently (but not sure where I put the spreadsheet for it) for like a FIFA Nations league. Open slather draw, the only rule was no more than 2 nations from a single confederation in a group (with the exception of OFC, only 1 per group)

Why were there so many byes? Did you include every country?

Run one with 128 teams.

I was speaking to my son about this last night. This would be great and because you're only playing 1 competetive match every 2 months your other tournaments and friendlies could continue as normal.  

So the way I worked it was similar to how first round qualifying playoffs work in the current systems.
Essentially the first round whittled down so that the second round had 128 teams (so the top ranked teams - with todays members (211) it would be the top 45 getting a bye to the 'second round' so that its 128 from there on.

Right. Understood.

In tennis how many are seeded for a tournament?

My understanding of the way they work is 128 enter the main draw, with the qualifying rounds/wild cards determined before that.
Once the draw of 128 is ready, there's 32 seeded players. Might be something else I'd be able to work in to hypothetical new draw (Top 45 get a bye to second round, but the top 32 are also seeded, meaning neither of them should be up against each other until the third round).

I'm not sure exactly how those seedings are determined, but I'm assuming that they're placed in the bracket so that theoretically the semi finals should be 1 v 4 and 2 v 3, etc etc, all the way back to the round of 32 (1 v 32, 2 v 31, 3 v 30, etc)

EDIT:
First, a random draw allocates matches to non-seeded players.Then the seeded players are placed. The No 1 and No 2 seeds are placed at the top and the bottom and the No 3 and No 4 seeds are put into separate quarters so none can play the other before the semi-finals.The rest of the seeds are divided into sections to avoid the higher seeds meeting each other, and randomly drawn between a limited number of possible positions.

So my understanding of that, is there's a spot in the draw specifically for Ranks 1-4 (to ensure that hypothetical 1 v 4 and 2 v 3 match ups for the semi finals), and then there's spots set aside for ranks 5-8, but these are randomly allocated. Same then for 9-16, and then 17-32. Everything else is open draw.

Ok finally sorted it!

To make it 'fair' I've used the FIFA World Rankings as they were for the first draw of this cycle of World Cup Qualifiers (Africa - Drawn June 30 2023).
So, what I have done, so that all FIFA nations take part, is the Top 45 ranked nations have received a bye to the Second Round (Round of 128).
To do this, 'BYE' was included in the draw as ranks 212-256, with 1-32 seeded beforehand as above (1-4 placed in their slots to ensure hypothetical semi-finals, 5-8 randomly drawn into similar slots, followed by 9-16, and 17-32). 

I have attached a PDF (not overly flash - sizing is weird) of the full bracket, but will also try pasting the first round matches later in a similar way to how I did years ago.

https://www.mediafire.com/file/hyg87sn9pzqw55c/FIFA+DAVIS+CUP.pdf/file

Quick run down of Australia's path
Round 1 - BYE
Round 2 - v Israel / US Virgin Islands
Round 3 - v Russia / (Yemen v Djibouti)
Round 4 - v (Spain) / (Bolivia v Uruguay) / (Kazakhstan v Singapore) / v (Estonia v Iceland)

And that's where we probably lose, so I'm not going to go further than that right now lol

Had a quick look. Nice one.