As to the original question, following your format, my criteria are as follows:
1. Quality of girls...I don't mind some variety in looks & ethnicities, I'm past seeking my 'type', knowing that many types of girls can be sexy. I do prefer girls aged 18-30 with an upper limit of 35 for the very well-preserved. I prefer slim girls, I don't mind a bit curvy if it's firm and she's beautiful, but no flab, cellulite or BBWs please!
2. Services...yes, as many as possible...but above all it's attitude...friendliness, willingness & natural responsiveness that sets the best from the also-rans.
3. Ratio/price...I am used to 2 hr 2:1 ratio parties, but busy parties are fun, so I don't mind if the ratio widens further as long as that's reflected in the price and maybe a longer duration. I don't see why parties in the provinces need to be more expensive than in London, almost everything else is cheaper outside London, so why not parties? I'm currently paying £140 for 2 hrs at 2:1 or £100 for 3 hrs at 3:1 with a well-known provider...I can't see why they need to be significantly poorer value than this, unless the providers are being greedy.