^^ That should work. This is exactly how my digital source upgrade path went:
I used to use a Philips DVD Player's analog outs. Then I added a Beresford Caiman (DAC) so I could use the digital out of the DVD Player. Then I ditched the DVD Player and started using a WDTV's digital outs. Next, I built a Music PC and used that. Next, I swapped the Caiman for a Rega DAC. Just last month, I added a Marantz CD5004 for use as transport with the DAC (for when I wanted to spin CDs without turning the PC and TV on). This path worked for me.
Now I'm wondering if I should have got a Mac Mini instead of the CD5004 and converted the current Music PC into an XBMC machine. That's another story there, heh heh.
Buying a good DAC will keep you flexible in terms of transport upgrades. You can use a Music PC/Mac Mini, or a CD Player, or both! And if you're using a good DAC, and you want to spin CDs, I personally think all you need is a fairly decent CD player with a good enough loading/spinning/reading mechanism (as you'll be wasting your money on the built-in DAC of the CDP otherwise). You really don't need to spend 35K on a CDP you'll be using as transport, unless the equipment downstream is really good -- good enough to bring out the advantages of a really good transport. IMHO, of course.