Possibly idle thoughts, but, if you put yourself in the following shoes…
– you have a racy-ish road bike (ie light, stiff, nippy handling) that you love everything about…
– …except it won’t take mudguards or a rack or disc brakes or larger tyres, all of which you want (primarily the guards and discs – not a common combination on light road frames)
– so you’re certain of your fit/position and can state precisely what geometry you want (albeit there needing to be slight compromises, mainly chainstay length) and what fittings etc you need
– you’re also a big chap, so can rule out skinny steel completely and would need a lot of convincing on steel generally; plus you might want an oversized head tube, ovalisations etc…
…whose doors would you be knocking on and why?