mj -
Welcome to TBN, nice first post. /forums/images/graemlins/smile.gif Congrats on the new machine, you're going to love what a Grand L can do for you. Is this your first tractor? I'm not sure what, if anything, you're going to be able to compare your 3130 to, but be prepared to be impressed with how much you can lift with that 723 loader!
Speaking of which, there have been MANY threads here on ballasting for loader work, I could dig up a few links if you'd like. Also, since you mentioned a trailer, I'm wondering if you're going to be using your machine for business? Either way (business or personal), I'd love to hear what you'll be using your tractor for.
On trailers: I trailer my Grand L, and a 4 1/2 ton, 18-footer does the trick nicely with the loader and a good-sized rear attachment.
Anyway, congrats again on a fine tractor,
John