Advice on compensating for hearing loss

Here's a puzzle: I'm an 84-year-old music/movie lover with considerable hearing loss (especially upper register), helped to some extent by high-end Oticon hearing aids.  Current system is an Arcam AVR300 receiver and a pair of Von Schweikert  VR-1 bookshelf speakers, old but still working well. What kind of additions/ improvements can I make that would at least  help with dialogue and lyrics and possibly even make music (classical, jazz, bluegrass, folk, rock) more enjoyable? A center speaker?  Which ones (since the Von Schweikert's can't be matched I've been considering everything from Polk CD10 to Elac C5 to Aperion 5C)? Would a subwoofer help? Anything else? I'm not much interested in surround per se unless it helps with the issue. I'm sure I'm not the only senior grappling with these and similar questions. Thanks for any and all suggestions.