What's your strategy for Bonus Heroes?

5:  Green Goblin.  It was OML, but since his nerf, I'm just picking the hero with my favorite kit / that looks the most fun to play.  I've got a fully champion'd 3* roster but not one champion 4*, so I feel like there's some freedom in the 5* space.  Sure, I should probably be trying to improve my 3/1/1 Thanos, but I actually want to play Goblin for fun.  I feel like the fun part of this game gets lost with how tedious progression is.

4:  Iceman.  I really enjoy collecting additional blues for my 3/5/1 Iceman, so I have him favorited so that I can wallow in misery at the useless bonus heroes I collect.  In all seriousness, though, I want to start my 4* transition with quality talent, as it were, and Iceman tops the list.

3:  It was Hawkguy, who was 1/3/3 three days ago.  Now that he's championed and earned me a Legend Token (sigh, Mordo Black cover), I'm going to be targeting 3*s based on their 4* champion rewards.  I think maybe Cyclops until I get the next cover there.  Should probably be Mystique, but I'm bitter because she's level 182 and the next level will earn me yet another blue Iceman dupe.

5* Black Panther and Hawkeye. It was BP and GG but after I got that yellow cover a couple days ago, I switched to him Hawk. I'm at 2/1/2 with BP, 3/3/1 with GG and only 0/1/0.

4* Medusa, Coulson, Wasp. It was Medusa, Carol, and Wasp but I just got Carol to 4/5/3, so I moved to Coulson from her. Wasp is 5/4/3 but I've got 3 yellow covers in the cache. I really need a blue or black. I'll champ her immediately. Medusa is 4/3/4. Moving along very well. 

3* Steve Rogers, Storm, and Hawkguy. I've got Steve at lvl 253. I get his BH covers more than anybody's. The rewards are so high, I just don't think I can miss out on them. Storm is now at lvl 221. I'm trying to push her to get that T4or yellow cover. And Hawk is at 1/3/3. I just really want more Hawk covers. 

DyingLegend said:

I select the 4* Bonus Hero that I am closest to full covering. Right now its Peggy Carter for me, but the annoying thing is, every time I get a bonus pull of her, it's blue, and I have a 5 in blue. Really annoying and frustrating as she is a 4/3/5.

5/3/2 here and my last 5 pulls have been red.

5* Thanos

4* Spider-Gwen (12 covers)
I have 9 4*s to champ, so I don't even think it matters at this point. 

3* Wolverine
I have been using the 3* closest to 266. After Wolvie I will switch to any of the 3*s that get covers from my 2* farm since most of them are at 220 and above. 

My roster is currently in the 3-4 transition -- almost all my 3s are champed (except She-Hulk and the new Hawkeye) but none have even reached 200. Meanwhile, I have about 2/3rds of the 4s rostered but most of them are 3 covers or less, and even the ones beyond that point, I'm stopping them around 150-160 until I decide who to push.

In the 3s, I'm still focused on unlocking roster spots, so I favorite anyone who is 1-2 levels away from generating HPs. (So 169-170, 177-178, 185-186, etc.). I'll also favorite anyone in the 181-182 range if I can use the cover I'd get at 183 (i.e. either already have the hero or expect to be able to open a roster spot soon enough to roster it).

In the 4s, three-pronged strategy: I'll usually favorite a) whoever's featured in the current/upcoming PvE event(s), b) all my 1-2 cover 4s, just to try to make them marginally less useless, and c) if I'm not too pinched on roster space, ONE 4* that I don't have rostered (Iceman, currently). Once I either have all the 4s rostered or some of them reach champion status, I'll re-evaluate.

For 5s, I don't really care at this point. Right now I have BB set as my favorite... just because... but I'm kind of indifferent.