From 1997 to 2015 my main commuter was a 1997 Nishiki Blazer MTB. Then it became my snow bike and utility bike with studded snow tires in the winter. For the other seasons, three years ago I put supple 26x1.86 WTB-brand slicks on it and it transformed the bike into a super fun, fast, but heavy bike. Last fall I converted it to drop bars.
https://www.bikeforums.net/commuting...ig-bouncy.html
https://www.bikeforums.net/general-c...converted.html
The one thing I would add to your list is gearing. When I bought the bike the gearing was not high enough for high-speed cruising. That was rectified by replacing the big chainring in front with the largest that would physically fit the frame (53).
Good luck, have fun and let us know how it turns out!