The first one by Cryo was great, mixing adventure with strategy and management elements. It's the only game of its kind I've ever played.
The ones by Westwood are all standard RTSs
Compare Avatar's and Titanic's numbers to any other commercially successful movie like, say, The Dark Knight or the Harry Potter movies. Cameron's movies absolutely crush everything else.
While, all in all, Lionheart is a very disappointing game, Barcelona is an awesome place. So, play it until you leave Barcelona and you won't feel cheated for buying Lionheart.
JE's combat wasn't just bad it was broken enough as to become pointless filler. And when the game's core gameplay doesn't work, it can't really be a good game.