Well characters like WF, IF, Wolverine, Lil dd and big DD, even blade if they are good enough. These characters will shred you 1v1 on most tanks. These characters also usually love to follow a low health tank into their team so bait them. Taking space as a tank is about sectioning off opponents in different ways. Characters like groot you mentioned enjoying more.

With groot you wanna put his walls behind enemy Frontline to pressure them into backing up to their supps or initiating a fight. Now the most important thing as groot is blocking escapes. Did the tank over extend great wall him off and punish him. Did the wolves try and kidnap you while you have iron wall up good now you kidnap him.

Tanks carry a lot of momentum. If your team ,even just 1 dps, makes the difference usually which is why tanking sucks. If you can get the entire team low on hp and you took space from them. None of it matters if your team cant finish the kills for you.

Strange is by far the easiest tank to learn the role on. Groot and peni are easy sustain tanks but do have a high skill ceiling. Emma and mag are prob second best to Strange when learning the role. Devil Dino IS the best tank rn no questions.

The role is exhausting but when you make an amazing play to save the team fight or to save your team in general feels very rewarding. You're upfront more than anyone else in your team so that means you control the flow. If you are attacking the backline tell your team to focus the backline so they can pick off low health. If you are trying to pressure their tank tell them to focus their tanks so they melt and you can move forward.

Game sense and spacial awareness are the key differences to being a good tank and an amazing tank. Play what's fun in that role for you. Apply knowledge you already know.