Is this old apple tree a suitable host?

It's been shaded in over years by the other trees, not as much sun as I'd like and it barely produces anything (I think I saw 1 crabapple this summer, leaves in 2nd pic), but it has an extensive root system. One way or another it's getting cut down, is it possible to graft anything new onto the trunk once we do? If so, is it a good candidate?

Thanks!