first, what was the intended size to beginwith? it's currently BoP K'Vort size, and that's on the lower end of the "frigalte" scale. for those of us on the older end of the fandom, thinking in the navy terms that Gene Himself was, works.
this is why I'm glad I though of my ships in actual physical dimentions as well as "class"
the Scythe is scaled the same as a BoP, currently. and, the B'Rel is a 12 person scout, the K'Vort (if I remember right) is a 50 person Frigate. you haven't said wether you've used the B'Rel or K'Vort for a size match
her's a general scale list
fighters
B'Rel/saladin= Scout
Miranda/K'vort/Rom BoP = Frigate
TOS ent/D-6,7 = light cruiser
TMP ent = Heavy cruiser
Excels /JJprise = "destroyer" (which was what it was apparently originally intended to be), later Light Explorer
Amby/ Mk II excel = light explorer
Ent D/Vorcha = heavy explorer.heavy battleship
1 KM and up should all be considered full on Warbirds
anything bigger than 3 or 4 km should be a world eater
anything at the 10km or more mark belongs to the borg, I bet.