<< I can install wooden threshold to try to blend in
with the wooden floor >><< What's your experience
of doing this? How successful that was? >>
Lived in a house where that was done years ago. Constantly had kids, family
members tripping over it. Most aggravating, dumb, irritating, and sorry looking
mess I've had to put up with. More skinned knees, spilled food, drinks,etc.
Older people and strangers in particular have major problems with such an
approach. If this happened in a business OSHA would be on your case in a
heartbeat, closely followed by the lawyers.
Dont be a wuss about the vinyl tiles. I can't vouch for all the adhesive
makers, but there always were much cheaper things to compound with than
asbestos. Pull up the tiles, find out in detail what lies underneath, and go
down to the subfloor if possible. Use a sensible respirator, keep dust down
with water and you'll be safer than driving cross town. Good luck.