Better version of Karma?

Hi, trash tier Silver player here in need of some advice. I like playing support quite a bit, mainly Morgana but she is banned often. When that happens, I enjoy playing Karma. I like that she has great poke in the lane phase and good CC with R+Q and W. Her shield helps out a lot in sticky situations as well, however I feel like late game she doesn't offer enough.

For instance, with Morgana her poke is also a snare, which I love, and her spell shield is priceless. Late game her ult can out right win team fights. I feel like she is solid all through out the game. With that said, I feel like Karma isn't quite as valuable the later the game goes. Her slow is decent when landed well, and her W can peel pretty well from my experience, but I just honestly feel like she doesn't offer enough (not near as much as Morg).

So my question, am I playing her wrong? Does she have just as much to offer late game as Morgana? Or is there a better Support that has a solid role all through out the game like Morgana with good CC/Poke? I know my item choices aren't the best, I gear towards too much AP when I should be building more support items, but kit wise I just feel that either I don't know how to play Karma late game, or her kit doesn't offer the late game potential like Morg's.

tldr; Is there another support that does what Karma does, but better?

Any advice is appreciated!