If you are doing AI.
Look at your budget, your cost of AI, vetting and so on...
Widen your search to look at conformation that will improve anything thrown by your mare, tractability, trainability, availibity do to AI, and then color and hair.
If what you find is more expensive or as expensive than your current choices, get pros and cons for both. If the pro's of another choice outweigh the ones you have chosen.
Go with those.
And for my 2 cents... Will the cost of this foal be cheaper with all of the stud fee, AI cost, vet care, mare care and feeding for her and then her and the foal, than buying a foal in the color, conformation
and type you want. Also do you have a buyer for any foal's by your mare?, Can you sell it in utero? Are these stallions you are looking at NOW, are their foals selling? Have the breeder's had to drop the
price? Weigh that with the market today and where it will be in a year.
How long will you have to sit on a foal/young horse in order to sell it? How far can you drop your price before taking a loss.
IF that seems like it is a losing battle...
Let you mare have a year off. Ride her, drive her, show her, get more use out of her than just a baby maker ( I am sure you are... but I don't know)
I only ask as it seems that certain breeds are a fad for a while and then they taper off into an every day thing.
Good luck and let us know what you decide!!