I just bought all suspension arms from Mr. T and that came to a total bill of just over 2.000£. I'm in Denmark, so things are a bit more expesive here. I would guess you could get them for 2k. I havent bought the subframe bushes or engine mounts though. The consensus on bushes is that you shouldn't go poly bush, if you want to keep the OEM feel and driveability for the car, but you sound like you are on the same page on that one from the start.
I can only recommend Chris' suspension. I've had both the OEM Bilstein J-spec, some aftermarked that was NOT working out for all the reasons you mentioned and now CWs fast road setup. That feels OEM quality and you can work with him on how much of a drop, if any, in ride height you want.
You could look into TRD sway and strut bars to sharpen the handling with OEM componets. I'm picking up a set of those as well next week, so come spring the car should hopefully be as handling optimized as at all possible with all OEM (I count CWs stuff as oem ) parts as possible.
That sounds like a path you might want to look at.