You can do both.
Ground team:
Gordon
Squishy
Jen
Tom
Johnathan
Reasoning:
You have no idea what the Iconian military is like, right? Maybe it would be best to not go in guns blazing. Taking the Recon and the Infiltrator would reduce the likeliness of being spotted. Should combat become a necessity, Jen, Squishy, and John have their sniper rifles and machine gun, weapon types notorious for pinning squads down (therefore making retreat easier). Tom may be able to identify whatever the object is.
Space team:
Calvyn
Big Red
Ulris
David
Tippy
Reasoning:
In the confines of a starship, close quarters weapons such as Red's cutting laser, Face and Calvyn's shotguns, and Ulris's swords would be valuable tools. Red's cutter could possibly slice through any closed bulkheads, and should all go well enough, Calvyn may be able to fiddle with the navigation systems to send the ship into the sun or something. If not, Tippy could plant a detpack on something important (or anything that looks important) and ruin the iconians' day in a less subtle manner.