I agree, hard to tell much from the pictures. The only thing I can see is that the bald face is adorable, which doesn't help you much I guess.
For your purposes (trails/pleasure) I would say that as long as he is sound, healthy and has a good head on him they he would probably be OK. Of course conformation is important but it is more crucial when we are using the horse for strenuous work such as jumping, barrels, dressage etc as those types of pursuits are more likely to put strain on any conformational weaknesses.
In the first picture of him with a saddle, he looks long backed to me and a little too steep of an angle in the front pasterns. But as you pointed out it's very hard to tell with these pictures.