hi Jzach, congrats on acquiring yr dream amps.
you wouldn't necessarily hv to use a pair of higher efficiency speakers if yr room isn't that big (although there are still benefits in doing so). however, i/o making wild speaker suggestions w/out understanding yr tastes/limitations/etc., i suggest you try better tubes on yr Ongaku to maximize them.
good GZ34 rectifier tubes makes a noticeable improvement across the board (metal base Philips Miniwatt are the best i've tried. they are sometimes aval. on ebay, but aren't cheap).
selection of input tubes (5687 & 6072) will depend on room/associated components/tastes. as for output tubes (211), i've found RCA superior to GE (more detail & delicacy).
good luck & enjoy yr Ongaku.
