68 Dart GT suspension upgrade recommendations - best bang for the buck

If it we're me with this car to start it would be in order

1. Welded in Subframe connectors
2. Offset Moog upper A bushing install for castor/camber
3. Good tires with modern tread design, traction and temp ranges.
4. Alignment for modern tires.
5. Good shocks noted above
6. Front and rear sway bars or at least stock front.

Drive and enjoy until your ready to step up to more if you want to.
If it were me, it would already be in a kazillion pieces and the wife would be giving me the evil eye once she got a look at the credit card statement...
OP- don't be "me". Stick to your plan and do a little at a time, enjoying it as you go. You've got some good starting points above, so do a little at a time. So some wise shopping and scrounging and you'll reach a point when you're happy without going overboard!