moomba
TheBrownDog
You need a rectangular stadium for football. West Ham might get 60k crowds but have struggled to create a good atmosphere in an oval stadium where the fans are a long distance from the players.
Then it's a compromise between fans being close to the action and those in the stands not being too far away to be involved. Plus the financials of building a larger stadium. Tottenham and Arsenal have built new stadiums catering for 60k fans. City and Everton more like 50k.
Ours was 47k when it opened, now 53k. Will be 61k with the current development.
Best thing they did when planning ours is have the first level underground. So when it was an athletics track that was actually where the second tier (ground level) is now, then they dug down and made it a more traditional football shape. Avoided that whole issue of seats being too far away from the action.