This is the way I like to build these champs. Building full damage would make them kinda useless because they stay in the middle of the action so they would die way too fast and building them pure tanky would make them even more useless because they won't deal damage at all. So I tried some hybrid builds with them and thats probably the best way to build them right now.
I really really like the 20%-28% bonus movement speed, because it makes it easier to join/leave the battle for them.
This is just a build not a guide, and of course you can vary it, if you are not satishfied with them.
Have fun