Ice and Bug do need a bit of a buff on the type chart indeed. I'd say Bug needs an offensive buff, like lose the resistance of Fairies or Ghosts, and Ice just needs an additional resistance, like Ghost.
Stealth Rock isn't that broken in the official formats I think, in the 3v3 singles and 4v4 doubles formats it's usually just not worth sacrificing a moveslot and a turn setting it up for a little bit of chip damage. It's just the 6v6 singles battles which are so switch-into-a-counter-and-predict heavy that kind of makes it broken, pokémon usually switch in and out several times in those battles, while in the official formats they usually switch in once or twice. If players have six pokémon in a team, they almost always have a pokémon in there that counters whatever the enemy has out and is a safe switch to try and get the advantage, and the switch is usually worth it. With fewer pokémon in a team that changes and switches are far less frequent.
You also see that happening in the 3v3v3v3 Royals formats. With only three pokémon in a team and three enemy pokémon on the field at once a 'safe switch' is far from a common thing. Manually switching isn't really something you do much in Royals. You can still switch, but mostly with Volt Switch or U-Turn. A pokémon like Tapu Koko or Manectric can use a fast Volt Switch to get quick damage and potentially a kill in and then hop to a defensive pokémon (like Alolan Muk or Incineroar) to take other hits for that turn. Incineroar has a slow U-Turn that doesn't do a lot of damage but does bring in a frailer fast sweeper (like Mega Manectric) in relatively safely because Incineroar has plenty of bulk. Stealth Rock is useful to slow down those kinds of VoltTurn teams, and Stealth Rock affects every enemy team with only a single setup turn, but you still don't see it too often in the Royals because switching without such moves is so risky.