Do you have a good english riding coach to help "train" you?
And judging by those pics you don't look big on her at all!
Honey you need to own your height, don't be ashamed of it, one of my best friends is 6'1 her hubby is 5'10 and she still wears stilletos when we go out lmao!
Stop slouching in the saddle, shorten your stirrups and get that leg in proper position, p I a n o
hands is a no no in english.
Personally I would rather ride a horse that is a blast and train WITH said horse then try a totally new prospect. Try her out she might just surprise you =) Don't get trapped into the WB/big horses are better circle, remember a well built horse with a great heart can take you everywere