If it doesn't sound properly balanced to you, then you probably don't have the correct RIAA EQ. Have you tried different records with different EQ settings?
I just have a simple setup for playing 78's... an old Dual turntable with a Grado 78 mono cartridge. I simply plug it into the MM phono inputs of my old Onkyo receiver and it sounds fine.
With RIAA for LP, 78's have a fat bottom end and are rolled off on top (if memory serves) but with a receiver, I can simply use the bass and treble controls to balance the sound to my taste (as I recall -- I haven't played 78's in a while).
AMC makes a tube preamp with bass and treble controls, phono input, and headphone output for only $799. It's the AMC CVT1030s, and I would think this unit would work well for your needs.
No special speakers or amps are required for 78 playback, but if you want to wax nostalgic you can always pick yourself up a nice pair of vintage speakers too.