Yes, but not versus endless waves of enemies that are vastly superior to you. If you're GOING to play that many battles, you might as well make it easy on yourself, or give yourself a fighting chance. I could play with 20 heavy cavalry and never lose, but 4 seems fine to me... my typical army is
4 velite
4 hastatii
4 triarii
4 equities
4 principe
If I'm auto battling, it's 8 hastatii, 8 triarii, and 4 equitites. Velites are useless in autobattle, and principe and hastatii perform similiarly.
Against waves of massively superior german swordsman, your auxilia will crumble instantly. I use them to pin the units, and have my cavalry demolish them. At least they're not companion cavalry
