A lot of raw power, but no finesse, and one huge vulnerability. Their weakspot is the power pack on their backs. It projects outward, making it an easy target from many angles, and, when they employ their special barrage ability, an easy target from all angles. As long as you don't turn your back on them, these guys are all blast and no burn.
A minor note: tanktroopers can automatically blast back any Agents in melee range. Few agents will want to be, but Scheherazade can still get in a combo or two before this happens, and Hardtack's weapon-stun (granted by a LEGION tech) can also be executed before knockback.