I'll throw out my anecdotes FWTW.
- Component allocation: I agree with some others that a large portion should go toward speakers. They contribute the greatest amount of distortion by far - that's a fact, therefore you'll want good ones. This isn't to say you want speakers with the most impressive specs on paper - such specs are often meaningless.
- Turntables: I think you've picked a good one. ~$1500 is where turntables really begin to shine. The MoFi and Technics 1200GR are probably the best current offerings in that range.
- Integrateds: I agree with others that it should possibly account for the smallest slice of your budget. There are many great budget integrateds out there right now. IME however, the Sphinx V2 is not one of them - not because of noise floor, but because it produces very weak bass at lower volumes. My local Rogue dealer agrees. The Yamaha A-S801 is better and fewer $$$. A used Exposure is also a good recommendation. I haven't heard it but the Outlaw RR2160 is an intriguing piece that measures well and seems to have many satisfied owners.
- Phono preamps: don't underestimate the importance of a good phono preamp. I've owned the Lounge LCR, and while it's good for the price there is much better performance to be had. Since analog will be your primary medium (or you think it will), I would at least get the LCR Gold or the LCR with Robert's factory upgrades (probably just have to call him about those). I was very skeptical of the importance of the phono preamp until I leaped beyond entry-level units. That MoFi package should be very well deserving of a $700^ preamp.
- KEF LS50s: They are not bright speakers - not anywhere near as bright as the typical B&W, Revel, or Focal speaker. I think those who claim they're bright are pairing them with subpar electronics and/or using excessive toe-in. KEF also recommends 24" stands which place them below ear height for most listeners. IME, when placed properly, they're actually about as warm as you're likely to find in modern speakers, aside from a very slight metallic overtone (as is the case with 95% of metal drivers). Most are probably using them with suboptimal placement. Until I got a pair of Tannoy XT6Fs, the LS50s were my favorite speakers under ~$3K. The $1500 Tannoys (with average dealer discount) now top my list of best budget speakers - which includes the likes of Vandy 1Cis, Magnepan 1.7s, and MA Silver 200s. This isn't to claim they're the best value out there, but the best value out of the many models I have experience with. They offer many of the LS50 strengths, but with greater bass depth and output, and none of the metallic overtone. The Tannoys also manage to produce good dynamics at moderate volumes, which is pretty rare among modern speakers in general.