I think he is over-hyped and was promoted too early. He will be overmatched next year if he lasts a full season and will struggle mightily.
I really don't know what his prospects for the future are. You read scouting reports about him that rave about his skills but the numbers don't back up the reports.
Here's a quote from U.S.S. Mariner I found interesting:
Lopez hasn’t followed anything of a normal development path. The scouting report on him has fluctuated between “defensive wiz who might hit” to “terrific bat who can’t field". His top PECOTA comparison is Adrian Beltre, showing obvious potential. Jorge Cantu and Luis Rivas follow in the next two spots, showing obvious risk. Miguel Cabrera follows them. So, the four most comparable players by minor league profile to Lopez are a couple of all-stars who could be hall of famers sandwiched around a busted prospect who is trying to resurrect his career and one of the worst players in Major League Baseball. Lopez defines a high risk, high reward prospect.
Here is the full post
which has a lot of good information on him.