My advice: pull to get 1 cover of each and then stop, get back to hoarding. Hoard your LTs for the next meta, hoard your CP for the next meta vault
It depends on your playstyle and who else you use frequently. I see some similarities between these two.Firstly, Killmonger also have Penance Stare like ability when the opponent match a critical tile and they have fewer than 5 red ap. This requires you to take damage just like how Penance Fare requires you to take damage, but you will deal back 300% or more damage back to the opponent. This percentage will fluctuate based on the opponent's level, match damage and critical multiplier. The only thing is Penace Fare has additional effects like destroying tiles, creating a CD or dealing random damage to non-target opponent.Secondly, Deadpool steals 1 ap when you match tiles in the target's strongest colour, whereas Killmonger increase your match damage in opponent's team strongest colour by up to 150%. Moving on to the differences, Killmonger creates 1 trap tile per turn when the opponent didn't fire a power. This could potentially create trouble for some of your teammates who create special tiles specifically on blue, yellow or green basic tiles. Secondly, your trap tiles can be overwritten when you are dealing with opponent special tiles spammers. Deadpool has a red stun that could potentially loop forever, but it requires someone who can shift specific tiles or create red tiles like Prof X or Storm. Killmonger can create 2 critical tiles which helps his passive ability. If you can team him up with someone who can reduce match damage significantly like BRB/Kitty or someone who can true heal, letting enemy match critical tiles is totally worth it. Imagine they make a critical match dealing 1 damage to you, and you deal 28823 damage back to them. Killmonger's Penance Stare is close to 30000%. But you have to wait till you champ them. since you are not in 5* territory, you are likely to meet a lot of Karnaks. Both Deadpool and Killmonger can deal with him. With the 4* meta shifting to Polaris/R4G, Deadpool is a better bet.Personally, I like Killmonger more than Deadpool.