That's a great drawing of your existing space. Here is some more info, for what it's worth.
1) So far nearly everyone has suggested the Perf Dlx. I say, get'em both and save yourself some agony. Which ever one you like the best, then put it in the place of best usage, sell the gasser (you won't use it much any more) and put the 26r MT where the gasser was,
2) You might be able to put four casters on the Performer and still maintain a level work table, but it's been my experience that the Perf, as is, is so easy to move it won't be an issue,
3) Now the 26" MT only comes in black, but black is beautiful -AND- those two kettles can solve almost any cooking situation.
SJ