hoosier audiofool

I have had a set of these in pristine condition for years and not used very often- I have a variety of speakers from B&W to Thiel to Vandersteen. Cabinets look new and so do all the drivers. I have Heresy's and Quartets, and have used dampening material on the horns to subdue the brightness on those. These 250's don't seem to have that issue but curious if they would benefit from some internal lining material, bracing (they are already robust and heavy), or anything else. I know about Crites and have upgraded caps in others, but curious if anything else would benefit. I have purchased rosewood veneer and will be veneering the cabinets even though the birch is perfect. I run these with a Vincent SV-500-either CD (Rega) or streaming, which may be the answer as to why they don't sound bright. Thank you in advance and for allowing me to be part of your group.