one other thing to keep in mind is that the clown loaches are schooling fish. They require at least three, but the more you have, the more you will see them. However, they get to be a foot long each, therefore, require a very large tank (at least 150g). If you have plans of upgrading for them in the near future, you could have them, otherwise, I would pick a smaller loach, like yoyos or striatas, something along that line.
jbarr, you said it better than any of us. You are absolutly right. You sure can have all of those fish together, so long as you are prepared for the circumstances. The blue lobster WILL at least TRY to snip your fish in half. That could be very devastating to wake up one morning to your dear JD cut right in half, and halfway eaten because of this blue lobster. And the clown loaches, and possibly the pleco (depending on the species you wish to keep) will eventually outgrow that tank.
If you want a stocking list along that line, might I suggest 1 JD, a school (6-8) of yoyo or straiata loaches, 1 BN pleco (they stay around 6-7"), and possibly some tiger barbs for dither fish (i would say 6-8) (someone correct me if I am wrong about the tigers being good dithers)