Honestly, based on these photos, this horse should've been gelded "yesterday". He may not be, actually, as ill conformed as these shots make him look... but I can't say that for sure, and, if you had to have my answer right this minute, it would be this " Tell your friend's NO" and go over all the many reasons why simply breeding a horse for it's color is a waste of time and money - if you like a color pattern, go buy it.
IF you can put up some good conformation shots of him, in good light, and they happen to reveal something that is "reproduction" worthy of him, or if he has a show record which PROVES he can perform... I would happily change that point of view. With the information and photos you've given though... snip snip.
Do your friends want to breed to him because they figure (or you will) give them a break on the stud fee... or simply because he's colored? If it's the fact that they want a "cheap" breeding, remind them - please - of the time and expense that it takes to produce foals. Then there's always the risk of injury or death of the mare, and/or foal... and on your side, since I'm assuming it would be some form of live cover, risk of injury to your stallion as well.
The rear shot indicates to me that this horse could use a little more fat covering as well - certainly before anyone considers using him as a stud. Breeding takes a lot of energy out of a stallion, so you most certainly don't want them starting lean. Use that as an excuse to your friends, if good common sense isn't good enough and doesn't reach them!
Again, if you want a favorable, or more favorable, feedback then post your horse looking his best, or show us some show records, or photos/video of him doing "something" and then we'll see.