Are monoblocks better than stereo, with tube amps?

I am only in the research phase of audiophilia. My present system includes a creaky NAD 150w amp and ghastly sounding speakers from a "rack system" circa 1988 Stalingrad. Anyway, I am hoping to eventually save for a tube set-up with a kind turntable and sweet, costly speakers. I am wondering if there is any advantage to using a monoblock system for amplification and why.