I'll be honest...my first horse was a draft horse...I had very little horse experience (very little) and I was like 16 years old or something like that. My draft has treated me well. Now, I am NOT saying that you should go out and get a draft horse because they are 'great' first horses for the inexperienced! M2G has good points!! You might want to start with a smaller breed...I think it depends on the horse.
Here is my 'personal' experience with my draft.
Everything is usually more expensive. Bigger farrier bills, boarding is more, supplies are more (because I need more), food is more (once again, because I need more to keep her ideal). The vet is more, worming is more. How much more, well....my farrier does regular horses for $40, I pay $65. That's not that bad but other farriers are worse. I have to use two wormer tubes to worm her, so that's double the price of a smaller horse. I'll just say,for me, personally, a light breed horse would be alot cheaper to own in general.
It's also hard for me to find things that fit her. I usually always have to order things (tack, blankets, ect..) 87" sheets aren't found in my local feed store.
My draft horse tends to need a lot of upkeep too. I can't just let her sit in a pasture...she'd fall apart. The flies love her! Her feathers need constant care too. If you got a non feathered breed, you wouldn't have that work.
I can ride and drive her. She's much better at driving though... She very mellow, but at the same time, she has a lot of perk to get up and go. She's fun! I've also noticed that she's an eye catcher (most drafts are). I always get compliments and such...she stands out!
I love my big goofy girl...she cost alot though...I'll have her till she dies and I'll miss her soo much when she does...I enjoy her alot!
I would say that, just find a horse that you like. Find one with an attitude that you like and can deal with. Find one with movement and build that suits your needs. If it happens to be a draft, GREAT!! Just keep in mind, drafts do tend to be more expensive in care...at least, that's my experience.
And don't let them step on your foot!! OUCH!!!