Aloysius isn't featless, actually. He effortlessly killed Tulak Hord's best Sith general, and was considered by Hord to be his fiercest and most feared rival. Some have even inferred that Aloysius was even more powerful than Tulak Hord in records.
Also, as a Sith Spirit he casually rag dolled an early Nox, and taught him everything that lead to him becoming prominent in the resurgent Sith Empire. He also was the cause of a mass awakening of Sith Spirits or something like that in the Dark Temple on Dromund Kaas.
He's pretty beastly, and his lightsaber is nice.