[71scgc]

Relocating the service will be the big issue.
Being in the basement severely limits the access.
As long as you can get to it, it's not such a big deal.
Relocation cost would be enough to make me leave it. I'm an electrician, I've done these jobs.

Working on old houses is like working on old cars. You don't know what you'll find until you get into it.
Your power company might have a problem with it since youre messing with the meter/service entry.
Many service providers have their own code which is much more stringent than NEC. Find a good contractor in your area. They'll know the deal, and may tell you what I just did.

Carter