Welcome to the board!

Need? The only thing you need is the kilt. Everything else is for look... but a sporran is definitely handy for modesty and pocket-space. A kilt pin will be handy if New Albany is windy. Hose and flashes? Your personal taste. Especially if you're just pubbing you probably wouldn't need them. I prefer the look myself, but Many don't. Ditto with the belt - it doesn't actually help hold up your kilt, just for looks. And the "belt" loops are apparently actually for the sporran strap, not your belt... and are unnecessary at that, even. Who knew? You can learn a lot from this site

That said, for "gotta haves", I'd say a sporran is about it, maybe a belt. Everything else can wait.

Get what fits you now. Never know if you're actually going to change size... and even still, most kilts have give one way or the other. Maybe not the thrifties, dunno. But then those are inexpensive enough to get you by until you are thoroughly addicted.

If you just want to know if you're going to like the feel of wearing a kilt, wrap a towel around your waist and go about the house for a while in that. Not exact, but might still get some clue of the freedom it offers. But you'll like it

Wear the tartan you like. If you want Stewart, wear it. Learn the history and "claim" it, even if it's only on speculation. Just wear it proudly!