Eyes positions, arms/legs lenght etc are not a problem.

Look here and find average proportions. Average people do not exist in real world, but we use it as a sample or description.

I think that average Poser figures are usefull, because it easier to create morphs. ADman is muscular then your "thin" morph looks weird, especialy his shoulders and neck, but I think it can be improved or ignored. ADman needn't to be all purpose figure. Fat and sedentary looks natural, smooth muscles are great.