Idk if you've actually given the game more than like 5 matches but the abilities are definitely balanced.
You clearly know when each player has their ultimate and even when they're using it, and specifically for the "rocket launcher" Raze loudly yells "Fire in the hole" when she is using it on the enemy team, something only a player that actually played the game would know.
Also if you are hit with a spycam dart, run over a tripwire, get spotted by sova's recon dart, or get hit with a recon from his drone, you get notified on the CENTER of your screen, something that again, only a player that actually spent time playing or watching the game would know. The arrow also glows bright red and sends out a pulse that limits its range, making it easily avoidable in addition to it notifying you if you do get spotted.
The drone glows bright red when it's moving giving you time to shoot it down. The spycam glows red while it's being used, giving you time to shoot it down. The tripwires are the only things that are hard to spot, but if you are shift walking, it makes a noise if you get close, allowing you to shoot it down or jump over it.
For anyone that actually played the games, the abilities are definitely not broken, they are pretty balanced, and the abilites that were broken were nerfed immediately. Riot is working hard and takes community feedback very quickly, unlike Valve who took 4 months to nerf the Krieg which the entire community had been complaining about for a long time.