Why not?
Don't ask me, I've been playing this game for 4 and a half years.
There are people like me who can stay with a game for a long time, but the fact is that many people just aren't interested in a game that starts very slowly and needs time and effort to make you feel like you're actually doing something.
It's not a bad thing of course, there's a market for everything, but don't expect BB to be the most popular game on the internet...
We won't have a tactical domination
There will always be one tactic/type of team composition that is superior to others. You can't avoid that.
What you can do is either to bring all tactics/team compositions as close to each other as possible in terms of actual success or to make tactics more into a rock-paper-scissors game, which has merits of its own but isn't 100% suitable for a game where you have a limited roster of players to work with.