welcome to the board

this wouldn't actually be a primary ob if indeed you contracted it 9+ years ago - it would just be your first obvious recurrence. how did they diagnose you as having hsv1 genitally? odds are actually that you contracted it from your current partner if you had a classic ob with multiple lesions. even the best blood tests for herpes we have still miss 1 out of every 10 hsv1 infections. it's just a lot harder to detect hsv1 on the blood tests we currently have than it is hsv2.
1) What is his risk of genital-to-genital transmission if we use condoms? Without condoms? Is it worth my taking Valtrex to decrease the risk if we don't want to use condoms? (He's had a vasectomy, and we are both STD clean otherwise.)
very low risk of transmission in general. usually just avoiding sex anytime you have anything going on genitally is all it takes2) What is the risk of my having type 1 oral as well? I've never had any cold sores or visible symptoms, but neither did my former partner. Is it likely that I have oral as well, or is the fact that I have genital mean I possibly don't have oral? If the risk is high, should we be using condoms if I want to perform oral sex on him?
most people who contract hsv1 orally don't get obvious symptoms. no easy way to know if you have it orally or not. since odds are you did get it from this partner, really not an issue anyways 3) I've read that HSV contagiousness reduces over the years. I got this many years ago, but just had the primary outbreak now. Should I still consider myself less contagious, or does this recent outbreak mean I am probably shedding more often?
contagiousness doesn't really change after the first yearbetsy