When batteries leak, try vinegar on a Q-tip for cleaning up the residue.
I've been using NiMH rechargeables for years in my remotes. I have 6 sets & 4 remotes. I usually have the backlight lit. I see no reason to go to anything more expensive.
RTR, a good tip, I'll have to look for them next time I go to Costco. Of course, here in VA they may not have the same products up in your Costco, to which I've been many times.