A lot of good points have been made about this ship's strength and how Kevin would change it to suit his interests. The first time the Enterprise engages it in battle, it is invincible, but only gives "love taps" even though it was capable of so much more. In the second engagement, it's obliterated by a single torpedo. Since these battles can't really be used as benchmarks for the ship's power, I must conclude that it lies somewhere in the middle of that spectrum. Since it's noted in the script that the Delta Rana IV ship is indeed supposed to be a recreation of the Husnock ship, and since it serves the story to have that ship be really threatening (I think the writers intended the viewer to give a little sigh of relief when the Dowd says he killed all the Husnock everywhere, as it would have been a real problem if the Federation had to go to war with them) I've decided that she'll be evenly matched with the SNS Galaxy X. This will make the ship a real threat to the standard Galaxy and the mid 24th century Federation in general, but it won't be unbeatable; a well utilized Sovereign would probably win. I think this will make it fun to use as well as keep it canon.