Need a tank support

I play Thresh, Sona, Lulu, and Morgana but I want a more tanky support as well to add to my lineup, I tried Trundle, but it's hard to get to adcs to get assists, Alistar is very good disengage, but I really don't like how weak he is overall he's like a walking CC that's it, and a lousy undependable heal. I want to be able to be aggressive but still be able to protect my adc, I like Leona for that regard, tanky, great initiation, great cc, and has a strong kit design to protect my adc, problem is she costs 4800 blue essence and I only have 4100 :( and unlike the old system, I don't get blue essence every game, so it takes awhile to build up again.