The 282 requires a NAPSC, in addition to the Hicap. With the 202, the NAPSC is optional. So if you’re going to get a 282, maybe just leave the NAPSC for now, otherwise you may be stuck with two.
I don’t think it matters that much whether you get an XPS or a 282 first. Your current system is good enough to show off any source upgrade you make. Personally I decided to upgrade my NDX by adding an external DAC rather than a PSU. Another possible option you could consider, but only you can decide which you would prefer.
Then go for a 250 and you will have a nicely balanced system.
I would leave the speaker upgrade until last, as what works with the upgraded system may be very different to what works for you now. Also, you will have a wider choice as the 250 will drive speakers that the 200 would struggle with.