I absolutely disagree. What if there is no box to teleport out of? What if there is no box to teleport into? It's a very limited ability to Dimension-Door into and out of a box. Metamagic is just a feat, and it's up to the PC to utilize the feat in a ingenious way. I can think of 4 different tricky ways off the top of my head on how to use a Metamagic feat. If you compare all my class abilities to your ideas and suggestions, it's obvious my class abilities are WAY more mischief and trickery oriented than yours are. Plus... My class abilities are FAR more than just metamagic feats and sneak attack, lol. I don't think you have played scoundrel, rogue type characters often or much at all. Or maybe you just don't understand just who Erevan Ilesere is.
CEC