Oh no, football is by far the most popular sport in Mexico. South American teams do do a lot better than North American at the CWC though, best placed finish for a CONCACAF team is 3rd. Still haven't been able to win it myself despite two appearances in the final. I haven't seen any Donovan/Beckham/Henry type loans even be considered, although I only have the NA and SA leagues loaded as playable.
It's quite a close league, a few good personnel moves can really turn a team around, so any team can be a possible contender even if they had a poor season the year before. I chose Seattle because they have great fans IRL and I would really love to travel there. Their youth recruitment is a bit restrictive to my goal of one day managing the USMNT to the World Cup, Dallas would probably be the best bet for that if I were to start over, but it depends on how you want to play. Big free agents are likelier to come to the big city, high rep clubs such as New York and LA. The advantages for the Canadian clubs is that there is an extra spot into the NACL through the Canadian Championship and Canadian citizenship is quicker to attain than US (3 years rather than 5) and Canadian players count as internationals at US clubs whereas US players aren't in Canada.
Sure, go ahead

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