I would go with a 8086k, 32 gb ram and a GTX 1060 of 1070.
No need for an Xeon or a Quadro card for Revit.

The problem with most branded workstations is that they are not made for Revit, meaning that when you want the highest possible CPU speed (what you need for Revit) you also get a Quadro GPU, which is not needed for Revit at all and most of the time you can not get the CPU you want. The 7700 is an older model, still OK, but why not get a 8700 or as Marcel says a 8086 (which is a great CPU for overclocking I hear from @REMISCS).

So, basically I agree with Marcel here and that is what I intend to buy when I upgrade my workstation

On your current systems, sounds like they have 64GB of RAM now? How much of that RAM are you guys using? Asking because it would make a difference in staying with a z370 chipset or x299

Hi Everyone

Thanks for the replies.

@ Remiscs, our workstations have only recently been upgraded to 32GB ram. The usage with our models generally hovers around the 20-23GB mark. we are aiming to future proof our workstations for the next 3 years with this exercise.

I agree with the higher CPU speed but that must not sacrifice stability.

Sounds like the i7 8700k/8086k with 64GB of RAM will best suite your needs. 3200mhz RAM is pretty safe now but if you were to keep it conservative, run the RAM at stock speeds by not selecting the XMP profile. 64GB now would be best because all the modules will be matched (buying a 64GB kit vs two 32GB kits). It is good practice to get matched kits but not really TOTALLY necessary in present day.

The 6700 is not very old but the current i7 8700k/8086k will offer some gains in performance. The fun part would be breaking into the 5ghz overclock with the 8086k but that is something that should be fully stress tested by your builder if overclocking.

You really do not need more than that. The 7700 is last gen and really would not be anything I would use in a NEW build today. It does not even boost as high as the 6 core i7 I mentioned; and with Revit you want clock speed. Now if the argument was a 7700k with it locked at the 4.5ghz factory boost speed; then yeah I can see that argument but the price difference shouldnt be so large unless they are selling you systems on clearance. Just get the 8th gen hardware if the price is similar. Also; the 7th gen i7 ran hotter than the 8th gen higher core count CPU.

Good luck!