>>Do you breed the two nicest animals regardless of flaws or do you look for complimenting traits?
If they have the same flaw, no. I tried that at one time, small stallion under 28", mares selected under 30", all nice, but a tad long in the back to height ratio. Not horrible, but ended up with small, pretty long backed minis. Not what I was striving for! So now I tend to be more critical on things like that, and definitely do take into consideration, similar flaws a no-no!
My biggest challenge with the limited breeding I do now is getting the smaller head (that actually has the smaller teeth, not a crowded jaw). That seems to be one of the hardest things to overcome from what I've talked with other Mini breeders.
What have you learned about selecting complimentary traits? Do you have to over-compensate in order to fix a flaw? Does it depend on the type of flaw?
>>You can't over-compensate. If you had super-fabulous stallion, he's not going to correct flaws/faults on mediocre mares. He can improve the overall quality, but likely will be faulted for not siring better than himself, while he wasn't given the opportunity to be used on mares of equal quality.
Small rant - over the years I've seen people promote and breed a totally awesome stallion to mares that are just so-so, or have no pedigree. Go look at the studbooks - Most stallions of quality have long, documented pedigrees, while the mares (usually the distaff line) are 1-3 generations. Pedigree isn't everything, the horse is what you're breeding, but if you start with an unknown, you can end up with ? Too much of a crap shoot, guessing game, imho. Minis have been bred for 30+ years now, DNA/PQ tested since 1996 (AMHA), so there's no excuse to NOT know what you're breeding or if the lines you're using are consistent in what they produce.
I'm not saying don't take a chance on something you think might turn out totally awesome. Over the years I've had some gorgeous foals from 'I think I'll try that'. But study your breeding stock, pedigrees and they're relations to see what does/doesn't cross well and if you can't see any reason it will/won't work, then give it a shot. The information is out there and lots of gorgeous Minis to chose from so there's no excuse for breeding horses with bad legs, weak butt/hips, foaling issues and definitely any sign of dwarfism.
>>Do you breed a mare with low tailset to a stallion that has extremely high tailset, or just one that is ideal?
Tailset is probably my most forgiving trait that I will overlook. Not ignore, but if it doesn't have the pin the tail on the donkey look and actually 'fits' the horses butt/croup (look at the variety in the big horse breed), I will not worry about that as much as I would legs, necks, heads, throat-latch, overall conformation.
>>Same for neck set?
I don't like extremely low neck sets, so do try to avoid those. I had a mare that had a low neck set, two breedings to the same stallion, one the same as hers the other like the sire.
>>What about a horse that toes out slightly - (assuming genetic cause rather than trimming)would it make any sense to breed to one that toes in slightly?
Toeing in/out if its genetic, I don't breed them.
Do offspring generally take on a trait of one parent or is there usually a blending or compromise of the traits?
Depends on the horse. Some are duplicates of one parent or the other. Most are a blend OR resemble a grandparent. I always take the grandparents into consideration. You could have an awesome horse out of a so-so one, and it might be the best it's ever produced while the rest have been so-so. I'd rather see a horse with siblings that are similar and/or better in a consistent look as you're more likely to achieve that look. Personalities - I tend to notice most of my foals get their sire's personality laid back attitude. Not all, but my stallions are total lambs, while I have some mares I think are in constant PMS. One, I had Bonnie Fogg evaluate a few years ago as I know the line to well, and she did tell me it was bad treatment to result in her craziness. None of her foals inherited it fortunately.