Should I make the trade?

Since this is a PPR league, don't do this trade. Gore gets plenty of receptions thrown his way and is of higher value overall than Reggie in my opinion. Your WRs in normal leagues would be on the iffy side, but being a PPR league, Welker will get tons of receptions for you as will Hines Ward. Both guys are possession receivers so you can't go wrong with that. Keep Gore, heck, even if it wasn't a PPR league, I wouldn't do this trade.