It'd be interesting to see the circumstances under which Lobo would be the #1 pick. Actually, taking the question seriously, Lobo with cloning or regeneration ability would be an amazing ally if you were fighting a force of multitudes of powerful individuals and/or beings with weapons that could cut through literally anything. He'd be able to even the odds, all other things being equal, in a HURRY ...
I suddenly wonder, now that the memory of a Brave and the Bold team-up with Supergirl actually happened in Mark Waid's 2006-2008 arc, and the unique talent of Lobo was to track a man even through a magic maze designed to throw of all pursuers, and Lobo's senses actually enabled him to defeat that, if Lobo is of use against opponents with shape shifting, invisibility, and/ or telepathic shielding and/or telepathic confusion in their arsenal. With a way to defend himself and others against mind control, and the aforementioned cloning and regeneration abilities, Lobo would be THE goto choice for, say, a full-scale invasion of White Martians ...
Gender: Male Location: Planning to take over the WORLD!
but it's unknown and there is no one on that list he comes even close to trusting as much as he trusts diana. i'd say there is NO scenario he'd take lobo. he can't trust him. supes is all about trust.
Huh? No one that comes close to being trusted like Diana? I mean, yeah, they were together for a bit and all, but I'm not sure that would translate to this situation.
I'll go ahead and say either Hal or Barry.
Orion may be a dark horse pick in this. Orion seems to be bring out the warrior spirit in Clark.
Gender: Male Location: Planning to take over the WORLD!
historically no other character save batman is trusted more than diana. recently it was revealed the 3 even have a secret code known only to the 3 of them in case 1 is in trouble. they aren't the trinity for nothing. imo this isn't even really close.