I am all for small watches, and while I don't think your 6430 is too small, it is definitely on the small side for your wrist. A 34mm Air-King is a great shout. Though, I'd always be tempted to spend a bit extra and get a 1601/1603 - 36mm, though, but that wouldn't be an issue with your wrist.
Prefer explorer 1s to datejusts, 14270/114270, but these are really expensive now. I’d wear a 34 watch daily easily even with my wrist and being super tall.
I like the turned bezels which is why I didn’t shout a 14000/14000m.
If I were in your situation, I’d wait, keep saving and get the Explorer 1. It feels like the watch you really want, the Air-King really is very similar to the Speedking other than size. Some early Air-King-Date’s are 35mm btw if every mm counts…
I am all for small watches, and while I don't think your 6430 is too small, it is definitely on the small side for your wrist. A 34mm Air-King is a great shout. Though, I'd always be tempted to spend a bit extra and get a 1601/1603 - 36mm, though, but that wouldn't be an issue with your wrist.