Hiya!!
Firstly, congrats on beating Season 2!! Just in time for S3 to start rolling out 
I’ll try to keep my advice concise (seeing as costume quest is about to start!!)
Purples - obvs no 5* so… Yeah haha. Tibs 2 probably before Rigard 3.
Yellows - with no Miki or tarlak, one could suggest Ranvir. HOWEVER, seeing as you have a maxed Wu Kong I’d personally not recommend this. I get into it a lot more in another thread but the short notes are that they do pretty much the same thing in buffing tiles… Ranvir just costs more.
So with that in mind (and given your excess of 4* healers) I’d probably suggest Leo. He’s a solid 5* hero. Not the best but not bad either. Joon would be preferable but he’s not there. LEO combined with your new jackal will definitely be killer. Add in Joon when he arrives and you got yourself a pretty deadly titan team.
Link to thread about Wu Kong vs. Ranvir:
Blues - Magni is great. Don’t really need Issy when you got a +20 Grimm. Mine is still at 3/70 for a long time and I only got Grimm +15. So yeah, just do Magni!
Green - horghall isn’t great… Even in rush attack tournaments… Just not enough of an attack stat to go with his DoA. Hang onto those tonics for another one. Either Kadilen or a second Lianna. Even Elk isn’t bad in a wing healing position for wars.
Reds - only reason for Ares would be for titans. Even then, BT +20 is probably better than Ares for a whole yet.
Azlar is deadly on rush attack but is also great in tile damage situations. So against titans & in events, azlar pairs nicely with Falcon, BT, Wilbur for the special skill. He and Elena actually have the highest base attack stat of the red 5* (including the extended new heroes) so yeah…