I wouldn't be against a like button in addition to this but I think then people would just give them out instead of merit and would be given too easily so I don't think they should actual count for something. I think the +1 merit button would be a good idea and maybe each time you click it it gives you an additional 1 merit every time. Would make things a little quicker and swifter rather than having to navigate to the new page just to dish it out.
Yes that's exactly what I was pointing out. +merit is like an additional work at the moment.
Btw, like abuse can be prevented by pegging it with the number of sMerit points an user has. If a user has no sMerits they won't be able to like a post.