I'm going to jump on the ASH bandwagon here. They were bred for this country, they take the best of different breeds and out popped a little Aussie Dynamite. They are versatile, and they're everywhere. It wouldn't be too hard to pick up a good one, and good horses are going cheap at the moment.
I would throw the Rocky Mountain Horse in the mix...
They are one of the more versitle horses that are being bred...
They were known for being able to pull a plow during the week, take 3 or 4 kids to their favorite fishing hole, and then pull the family to church on Sunday in their buggy.
Now they are known for being excellent trail and show horses. RMH have a willing attitude and will take on anything you throw at them. RMH are showing, trail riding, endurence riding, jumping, dressage, and one trainer even competed and succeded in the Extreme Cowboy competition with a RMH.
I vote for the Quarter Horse as well. They have the best temperament, and are very intelligent. Most of the stallions I've been around are great as well. I knew one that could put his head down and nibble grass while under saddle, and completely ignore mares that were close by. Years ago I worked at a stallion facility, and the QH stallions were on a whole easy to handle. Other breeds were mostly a handful, and some were very dangerous. Just a generalization folks, I know there are good and bad actors in EVERY breed.
A note: I finally figured out how to put an avatar on my profile. Yea!!
Arabians are VERY versatile. At the US Arabian Nationals you'll see an Arabian showing in every discipline you can think of. I agree, some can be quite crazy and spooky.....but most are very level headed and personable.
QHs - Yeah, they can do a lot, but I just don't think they are as personable or "happy" (for want of a better term. Lol) as Arabians. They seem more standoffish. I like to think of them as the Work horse of America. They were bred for work, and that's where their mind set is. They are really cool and I like to ride them when I've got to chase cows or find a lost calf...other than that, I like the Arab personality better.
Morgans - Very cool horse! I've never actually worked with one though.
I'm new to the Aussie horse, but I really like the looks of them! They look really nice.
I like to think that any horse can be relatively versatile. A horse is a horse is a horse at the end of the day. A TB can chase cows, an Arabian can jump, a QH can do dressage, a Morgan can barrel race, a Percheron can pirouette, a Friesian can show western pleasure, a Shetland can, um, be a Shetland. LOL.
They were bred for work, and that's where their mind set is. They are really cool and I like to ride them when I've got to chase cows or find a lost calf...other than that, I like the Arab personality better.
I will agree that they can be standoffish. Riding is work? Actually alot of QH's don't want to chase cows, it takes a special personality for that.
Roro, Yeah appendix are nice, it depends on how much TB the horse shows. We have alot at the barn, half are more QH and are great. The other half are more TB and wouldn't do so great in alot of the western classes (like reining, cutting, eta..).
Bashkir Curlies. As their quote says, "Gentle enough for a child, strong enough for a man." I have seen them participate in a number of different discriplines. Their body types vary, especially when they are crossed with different breeds. They have strong feet, incredible endurance, and amazing heart.
I agree that individuals will vary, and bloodlines within each breed will vary as well.
Overall I would say Appaloosas. You can find Appaloosas excelling at many events, and you can find/continue to breed various blends of QH/TB/Arab bloodlines-- the top-named breeds so far in this thread besides ASH-- as well as "foundation" Appaloosas which are more old style and usually bred App x App to preserve family type dispositions and soundness and stamina.
Lots of choices with Appaloosas, plus the added bonus of unique coloring and patterns, as well as more sedate and/or solid colors, depending on your preferences.
Spruce meadows in Calgary, Alberta, Canada hosts the Telus "Battle of the Breeds" each year-- A team from each breed competes in Jeopardy Jumping, Trail Riding, Barrel Racing, Precision Driving, and Compulsory Skills. Here are the winners over the years--
1990 Team Paint
1991 Team Arabian
1992 Team Arabian
1993 Team Arabian
1994 Team Thoroughbred
1995 Team Arabian
1996 Team Canadian Sport Horse
1997 Team Thoroughbred
1998 Team Appaloosa
1999 Team Appaloosa
2000 Team Morgan
2001 Team Morgan
2002 Team Appaloosa
2003 Team Appaloosa
2004 Team Appaloosa
2005 Team Welsh Pony & Cob
2006 Team Conemara
2007 Team Appaloosa
2008 Team Mule
2009 Team Morgan
As you can see, Appaloosas have won more than any other breed. They have also has some close seconds and many top 3-5 finishes among the 13 breeds competing. Here are some photos from the event over the years---