Le Cellier is 1 TS credit until March 1, so OP is fine on credits for that meal. The only issue there will be that you will totally miss Illuminations (not a chance you'll be in and out of there in time with that time meal...which is why it was available.) ...if that was your only chance to see Illum. you might want to skip Le Cellier - it's good, but not good enough to miss Illum. unless you go to Disney all the time and have seen Illum a kazillion times. If you would like to see Illum. though, and you're really wanting a steak that night (assuming you'll be in Epcot that evening) I might suggest you try Captain's Grill over at Yacht Club (you can walk through the International Gateway over by England in Epcot to get to the Epcot resort area, then come back in that way after dinner.) Chances are you could get an earlier dinner reservation there, and they do have steak on the menu--we had two different steaks there last year--pretty good food, great service, and not nearly as crowded as Le Cellier and other Epcot restaurants. And then you can get back to Epcot in time for Illuminations. If seeing Illum. is not high on your priority list, then keep Le Cellier...we love the steak there. Another fun place to eat in Epcot with kids is Biergarten (and being a buffet, can usually find something to please everyone.)
We didn't love Boma dinner at all...lots of "interesting" spices going on there (like the BBQ ribs...aren't really what we'd call BBQ. There were slathered with a sauce that tasted like it was made from Red Hots candy...like sweet & very hot-cinnamon taste. Ugh. But to each his own. Lots of people think Boma is wonderful.
Chef Mickey is great for characters...but the food is just so-so. However, if you want the Fab 5 character pictures, that's the place to go. With an early seating like that at least the food should be hot and fresh.
We really like Crystal Palace (all meals) and again, we enjoyed the characters there. Like Mama Melrose too...although we have had very slow service 2 out of 3 times at Mama Melrose, so be prepared if they're still slow (have seen many reviews saying same thing, so it's apparently how they operate there.) But we really like the food.