ARFs can certainly be of poor quality and take work to make them right. I think the dihedral is fine and not the problem. It is hard to see how far off the wing is from fitting in the saddle. Would the wing mounting screw align up? Is there suppose to be rubber installed between the saddle and wing to fill in the gap? The aileron problem does look far enough off to be a problem. The only way I can see to fix that is try to bend the ailerons until it matches. Be very carefull in that if you do this not to break them. The wing and stabilizer alignment does happen and you will need to sand the saddle of one or the other to get it to match.