With the sizes they are at right now, I don't think you are in that rough of shape. However, if those fish all end up living long, happy lives, they will become too big for that tank.
If you didn't have the clown loaches, I don't think it would be that bad. Do you think you'd be able to get a 55 gallon tank for them once they start getting bigger? Or do you have a friend or lfs who could take them? Whatever you do though, I would not add anymore fish. Genie had a good suggestion with the ottos instead of the pleco. I probably should have gone that route, but I love common plecos so much! I figure I will enjoy him for as long as I can, and if he gets too big, I have a nice lfs that would surely take him...as much as it will pain me to part with him, if we reach that point.