Help Putting Together My Next System

Hi. I am getting ready to put together a system for myself and could really use some advice.
What I listen to: Lots of Alternative (loud), Old Jazz, Classical and some Classic Rock.
Equipment I have to possibly incorporate into the system: Marantz 8b, Mcintosh MX110 & a lower level McIntosh tuner/preamp.
My goal: Build a system for listening to digital music files. No home theater stuff.
Current System: Yamaha CR1000 Receiver & 2 B&W 500 Series Towers. All purchased new, I keep my stuff a looong looong time. Maybe too long!
Here is what I am thinking (but not at all set in stone): Purchase 2 B&W speakers possibly from the Nautilus line and probably used, use the Marantz 8b amp and the McIntosh MX110 as the preamp. Possibly biamp the speakers using a solid state amp for the low end and the tube amp for the mid/high end. Have no idea what I'm talking about but thought the tubes would give a nice warm high end and the solid state amp a tight base. Don't know if that even makes any sense.
Questions I have: Does it make sense to utilize the vintage equipment I have (stored for over 25/yrs)? Any recommendations on experts to go through the equipment (I live in Orange County CA)? What type of digital files should I use for building my library. Everything I have is on iTunes as mp3 but will build a separate library for this use. Any software or hardware to handle these files?
Most importantly though what recommendations on the system as it will likely be my last (I'm 53yo). Cost is important. If I could stay around 5K using the equip I have great but would be willing to spend 20K plus (would have to spread that out over 3-5yrs is I spend that much).
All recommendations and opinions are welcome and greatly appreciated.
Thank you to everyone.