Plus with all that mass from the engines the turning would be hampered enormously.
Nah sorry, We're in space. Mass doesn't do anything, there's no gravity or those kinda things. And, if it would have weaker weaponry, that's a good weakness enough.
What I'd like with this ship would be a "ion cannon" just as in Star wars. The ion cannon is used as some kind of an E.M.P. weapon that disables ships. In fact, I'm going to suggest this weapon.