Well if you're looking for realism, science fiction probably isn't your best bet. As technology gets better things have a tendency to get smaller, not larger.
Prime Universe Star Trek had ships that dwarf anything in STID. When Archer goes to the future, he's aboard the Enterprise J - probably the biggest Enterprise and maybe biggest Federation ship ever seen. Thing is two miles long!They are not fucking huge, they are ridiculous.
But hey, let's face it, it is now "canon", so ST is now ridiculous, and you liked it, you embraced it, it is over and done for ST.
http://en.memory-alpha.org/wiki/Enterprise_J
The Neghvar Scimitar or a TNG era Warbird are both bigger than the Nu-Enterprise. Calling foul on large ships in Nu-Trek is just picking something to bitch about.