Single Spey,
The PRIMARY task of Aberdeen Approach Radar is to provide a Radar Control service to aircraft operating inside Controlled Airspace.
If time/workload permits then a SECONDARY task is to provide a service to aircraft in uncontrolled (Class G) airspace. The fact that those Class G flights do normally get a RAS from Aberdeen is purely down to the dedication & hard work of those same ATCO's. If you want to beef about service provision then your beef would be better directed to the management at the Scottish Area Control Centre, who some time ago (and following a very nasty Airprox) took the view that providing a RAS in that part of the sky was too risky - from an organisation point of view - and placed their Controllers in a legally risky position if it all goes pear shaped. Therefore SCACC ATCO's only provide a RIS, whereas Aberdeen provides a RAS - for now.
This is directed more generally about those who operate in that area - if, as keeps being said, P18 was there H24 then they would use it, WHY do inbounds keep pressuring for descent clearance which then takes them out of the bottom of the Airway - to the extent that it is becoming common to hear "request further descent, happy with a RAS outside"! might as well scrap the airway altogether
IF the base levels are too high for your flight profile - file a report. Nothing will change unless enough pilots put in the paperwork.....
Finally, "Zig-Zag" vectors are a necessary tool to fit you into a traffic sequence - you know, thats the other 7 or 8 aircraft trying to land at the same time as you and all arriving from different directions. 450+ movements on weekdays at an airport the size of a penny black makes the odds of a straight-in much less likely - accept it and stop the little "huffys" when told to slow down and turn left.
Safe flying
DD