Nice example of how one photo tell littke about whole thing. Video of Sukhumi
Also worth mentioning Batumi is rich port city while Sukhumi was small resort place even in Soviet time.
Pouring billions of dollars on Chechmya is better then pouring bombs, i think. There is no Sharia law there by the way, despite they (and other traditional Muslim places) are far more conservative then central Russia.
I could easily choose photos that would make my own city look beautiful, it wouldn't be too close to reality though. (Although it's getting better, sure.)
Even in the video you posted, the areas close to the sea look like shit, in a place with otherwise enormous potential to attract tourists.
Conclusion: Russians played active role in Abkhazia's separation from Georgia (including ethnic cleansing of the largest ethnic group - Georgians, which were IIRC majority in the capital) and then left it to rot, not even recovering it to pre-war prosperity.
Btw. just google 'sharia law in chechnya', there's a shitload of examples by how Ramzi implements elements of it.