Re: What improvements / new features would you like?
1. Like many others have said, statistics make this sort of thing far more interesting. Specifically the players; cup stats should be recorded as well as league stats, and there should definitely be player award histories on their profiles. This should also transfer over to the club history bit; we have highest transfer received, why not highest goal scorer? Highest rated? Most reds? Most assists? Etc. You record all these things, so it shouldn't be too hard to add them on to that bit.
2. Player limits: It's just silly at the moment. People have like 300 players in some worlds, why? It's so unrealistic it's crazy, and I think that's the problem, realism. Exact realism is bad, but in instances like this there should definitely be an attempt to make it better. What club in the world has 300 players? It should be capped, I dunno at what. You could say 50-60ish (as you need a first team generally of 25-30 + a youth team. Some people completely dominate worlds, there's no point joining them as they have all the best players and allthe best youth.
3. Inactive managers need to be dealt with. This causes so much trouble in smaller game worlds. They sign up, get given a team in a league that's starting soon and never sign in again. I understand that you want to try and get people active, but you're not paying enough attention to the people who are active here. Waiting 30 days for a manager to get kicked (+7 for their players to free up) only to have to wait another 30 days when a new manager joins is awful. The time limit for new managers getting kicked if they're inactive should be much, much shorter. Personally, I would put it at 7 days. But, of course, another person who will go inactive can then take the team over, so I'm not sure how you stop that.
There are other things I'd like, such as more tactic options and a reserves tab for the squad, but these three I think are the most important (especially 2 and 3). I have a lot more things I'd like tbh! It'd be good to have more regular games in every league, then people would require a good squad not a good XI. Okay, I'll stop!