I second the use of a pair of B110 based mid range book shelf speakers like the Cantata, Concerta, Cresta, Coda I&II, etc, put in parallel. Next in line would the more modern B200 based mid ranged speakers. If space and wife permits, best use the excellent mid/tweeter/mid section and the cross over part of a dented/cheaply bought KEF 104/2 or just plainly place the entire speaker horizontally.
I recently changed my 5.1 HT setup from Maggies/Snell Acoustics to a fully restored KEF 107(refoamed all woofers, replaced most caps in the crossovers with polypropylene caps with metal film, resoldered all on boards and connectors with Cardas silver solder and a lot of wood staining) as fronts, KEF 104/2 as center and surrounds (it took me a while to match the wood/finishing and colors of all speakers).
All that out of love for great sound and KEF nostalgia.