The glass isn't necessary and a lot of people are moving away from it due to safety concerns.
+1. If you want to see the fermentation in progress (which I think is a good thing especially in the early days), I recommend PET (plastic) carboys. Lots of people use these with great success, and they're cheaper than glass.
If you plan on going directly into kegging you should probably buy your equipment piecemeal because you won't need the capper or bottling bucket, which is almost half of the cost of the kit.
+1. I started out kegging as well, and felt like I was able to maintain motivation to do more batches because I didn't dread the bottling process.
I looked online at kits from several of the popular online shops (MoreBeer, Midwest Supplies, Northern Brewer), but most of them either include bottling supplies (which you probably won't want) and some other odds and ends that are not what I would recommend (i.e. I do not recommend the "one step" cleaner/sanitizer that's included in some of the kits).
Maybe someone can point to an existing sticky or thread that lists out "the essentials"? Some of the stores I mentioned do have separate "kegging kits" that should have everything you need to get started kegging. Just do some reading on pin lock versus ball lock and make a decision on that so that you can standardize. I started out with pin lock (because it came with my starter kit), but later ended up switching to ball lock so that I could purchase brand new kegs (all pin locks are refurbished).