Siege really does need love. It used to be my favorite game and now I can hardly stand it. Let me count the ways...
* So many unbalanced maps. The newer ones often aren't an improvement, with some really simple, nearly impossible to counter ladder bridges that take attackers from spawn point to flag inside of 15 seconds. Meanwhile defenders often spawn 20 seconds away from the flag. Some maps are 0-3 every single time.
* So many "unfun" maps. Maps that just have no strategy to them because there aren't any chokepoints, or if there are, the ones within 10 feet of the flag are the only ones that make any sense.
* 1st round attacker advantage bug. Ugh. Yes, I know the trick to avoid being put on defense on the 1st round. It's still annoying. And the trick only works if 50% of the people don't do it.
Really the only thing keeping some of the maps from being a complete waste are that 80% of the players don't understand them and insist on taking the long way through the map rather than the map ladder here and the medium ladder there and bam, you're on the flag.
Maps with doors that can be opened from the inside tend to be particularly annoying, as it's often easy for attackers to bypass them and they end up hurting the defense as much as if not more than the offense.