As someone who has left and come back three or four times since season 11, I personally wouldn't want it to change. I've seen a good many additions and changes with each time I've come back to the game, and every time, there are things I like and things I think in my head, "why?"
I may be addressing the wrong end of the issue here with the suggestions to improve building rather than eliminating it, but here are my ideas:
1. Speed up the build process, and eliminate the randomness element of it. I do enjoy waiting to see if my "completed in 2 days" project will be ready in time for my league game in two days or not, but knowing that it will be allows me to place an order that I'm confident the seats will be ready in time. Also, I propose an increased rate of 33% (i.e. What was once a "6 days" project would now be "4 days", 7->5, 10->7, etc.)
2. Rather than giving new players a free arena, let players build as they will. Financially, learning how to make money and be competitive is part of the game. I'm managing just fine, I see several others in my division are picking up on it, and the ones that aren't are the folks that registered and disappeared. They'll reset again soon enough. However, if you're concerned about players choosing to be competitive early and not having an arena capable of sustaining it at all, here are a few options:
3. The $50,000 weekly bonus for new players can be made into an arena upgrade voucher for $50,000 in free construction. It is not a lot of seats, but if it can only be used for that purpose, that's at least a good cheering section each week being added on, or wasted.
4. Implement an "Arena Size Floor". Roughly what I'm picturing is that, when a player starts, said player receives a roughly 6k capacity arena. Set a size floor for each division wherein it can be described that "In higher divisions, more fans are taking notice and becoming excited about your team, and about the team's you're facing! Make sure your arena can support that increase!" Basically, if the arena is below the Size Floor and there aren't additions being added, slowly even what's there will stop selling out because too many fans will be left standing outside the arena angry that they can't come in to watch the game and those last few fans will start to worry they won't get seats either, and thus start to leave before they can buy tickets or come inside. And it becomes gradual up to maybe a 20% current capacity range. The floor would work as follows:
Starting Division: new arena
Starting Division +1: 8500 seats
Starting Division +2: 11000 seats
Starting Division +3: 13500 seats
Starting Division +4: 16000 seats
That way it becomes based not on the Division you're in, but on where teams in your country are starting. It seems completely unfair to require 16000 seats for a D1 team that started the previous season in D2 in an unpopulated country.
Probably needs a lot of refining or work to implement, but it's an idea; regardless of that idea, I do quite like the "arena voucher" idea as opposed to free cash.