it's funny having the retrospection to see many of these complaints levelled in the opposite direction
I always wanted the marines to match up to their cool (if self applies) moniker of "ultimate badasses" that doesn't mean nerf xenos to the ground or make them not a threat, in fact them being so dangerous and lethal is what could define the marine's strength by contrast, while the xenos are mysterious, uncomprehesively effecient, and unpredictable, the marines are strong, tunnel visioned and with the combined firepower no other infantry faction could hold a candle against save for the UPP
don't nerf marines to make it balanced, buff xenos, make them both super deadly, scary enemies that nobody would ever want to fuck with, the marines could completely demolish any foe it set its undivided attention on, and the xenomorphs can easily and effortlessly destroy any individual unlucky enough to be in their path, with abilities catered to psychological and biological warfare