As others have pointed out, the rules (certainly for the UK) are clearly set out in the national procedures manual. It is unfortunate that at aerodromes where RW mix with larger FW operations those procedures do appear to penalise the RW operations, in some cases quite significantly. Sadly, simply being unhappy with that and posting here doesn't change things. But there is a process for changing things, at your home base, at least, if your ATC people support it. Many national procedures can be varied to take account of local conditions and features....if the variations are published in the local Manual of ATS. To get something into the local procedures it will have to be approved by the CAA and I imagine this will require something along the lines of a safety argument showing that the variation is at least as safe as following the 'standard' rules. Whilst this takes some work and effort, if there are benefits to be gained by both RW operators and ATC (and, probably, the airport), maybe it's worth doing. I've no idea how such things are viewed these days, or how practical it is at your base and with your aircraft, but there may be other possibilities which do not require some of the separations to be applied. In the past I recall one airport where RW (although not larger ones) hover/air-taxied from the apron to a designated point in a grass area, from which they transitioned and set course largely as desired. The point was quite specifically not a FATO and was outside the runway strip - no wake turbulence separation is specified and a caution was issued if the aircraft was going to pass behind or through the recent path of another aircraft. Seemed to work OK, I'd go further and say it worked well for everyone, but maybe it's been stopped in the intervening time.