Here are my Picks, and my reasons why.
I tried to keep my team original, by the way, and not overpower it too too much.
Distraction - Deadpool (Because he is an agile skilled fighter, who cannot be killed, and regenerates almost instantly...Sure hes going to get beat around, but what better to keep these three busy? Theyre just going to keep attacking him and trying to kill him.)
Leader - Xavier (Who better than Charles himself? He can keep these guys at bay with his telekenetics, and has been proven time and time again to be an excellent leader.)
Long-Range Assault - Cyclops (I hate his character, but his optical blasts can reach the moon, and he has amazing aim. He has also shown his blasts to be powerful enough to knock God-Like characters off their feet.)
Close Range - Strong Guy (You'll see why, read the supporter.)
Supporter - Gambit (Not only can he hit these 3 with his Kinetic energy blasts, Strong Guy can absorb kinetic energy to the point where he is strong enough to be on par with all three of these strong guys...Gambit can constantly fuel Strong Guy with kinetic energy, since he is immensly powerful while absorbing it, but needs to refuel quickly, Marvel has said strong guy, which a constant supply of Kinetic energy has durability, regeneration, and strength enough to take on Hulk.)
Informant - Cable (Not only can he help support, with his weaponry, he can use his telekenis to relay messages instantly, who would be a better informant than a psychic?)
The first pick of my Choice would be Warpath, just because he is plain cool, and in the 100 ton strength category, and his knives cut through almost anything. And my second would be Jubilee, for her ability to keep these guys blinded.
Strategy: Okay, so Deadpool distracts, gets pummelled to hell by these three, but it doesnt matter, because he can regenerate infinatley, hopefully in the meantime he deals a little damage to them. Jubilee CONSTANTLY keeps these guys blinded with her fireworks, while staying out of range. Xavier keeps these three occupied in the mind, and uses is powers to keep them contained when he can with his force fields. Gambit attacks these guys with his Kinetics when he can, but primarily attacks strong guy, who absorbs his Kenetics, to keep him powered up, and he engages these three, hopefully knocking them around quite a bit, while Warpath literally cuts them to pieces. Cyclops attacks mostly from afar, while hes not going to deal a ton of damage, he can certainly knock them down, and keep them off balance, and hurt them a little...Cable deals damage and helps occupy them with his weaponry, while being the "informant" using his pyschic powers.
Hopefully, cable, gambit, jubilee, and cyclops would keep these three off balance, and off guard most of the time, while deadpool keeps them busy and distracted, while dealing some damage, So that the constantly fueled strong guy is free to kick the stuffing out of them, and Warpath can rip them a new one (literally) because Xavier is also occasionly blocking attacks, and holding them in place when he can....)