Spent my drive home yesterday pondering if the Emperor 5A would have been 'good' to be more common and around in the 3SW era. DPS barely above a medium mech, slow, well armored & sinked, but it has a bit more mobility with the JJ. I mean for PCs, it is a great way to give them a assault, though it is barely more useful than the Small Laser armed Charger. Unlike some of the later '3025' era designs, I just do not think the Emperor 5A breaks the setting.
I mean, if I got it as a merc . . . probably the first thing I would do would be swapping a single AC/5 for a PPC or LL, cut down on ammo and increase ranged damage with the sinks to actually use the weapon. Tossing the JJs is also a open question.