TB's and TB Crosses. No way around it. They are versatile, athletic and just have the drive to do it all. Ideal event horses are light. The thicker horses are great for lower level stuff but just don't do well at higher levels of cross country.
My current horse is a Belgian WB/TB cross. She is a bit brain dead at times

But she is just a great attitude and loves to work. I haven't actually had her out cross country yet but we are planning to this summer. She jumps like a dream and pulls off a fantastic dressage test. I think she is going to love cross country because she has the work ethic and thrives off a challenge. I am really excited to take her out.