A lot can depend on the time of day your online, despite 777 studios stating they have more North American players on the books than any another country, European peak time (evening) still seems to see the highest numbers online (I don't know why that should be).
I know what you mean though Rich, flying against only one or two other players isn't that much fun, remember though ROF is not MMO, you won’t see numbers in the hundreds, 10 to 15 is more than adequate for some fun flying though.
The servers are all privately run (777 studios don't run any), the six main dedicated servers being "Fast Food", "Flying Circus", "Les Hellequins", "New Wings", "Syndicate", & "Oceanic", a ping of around 150ms or less should be good enough to play on any of these.
You can check the numbers online and players ping times on this web page:
ROF Online ServersAs each server is independent, each has it's own Scores & Statistics pages which you can find here:
Flying Circus Server Statistics (Server similar the AH WWI / furball lake with icons)
Les Hellequins Server Statistics (full realism Server, no icons)
The Syndicate Server Statistics (full realism Server, no icons)
Fast Food Server Statistics (Server similar the furball lake without icons)
New Wings Server Statistics (Server aimed at those just getting stated in the game)
The planes available on each server varies a bit and changes though out the day, if you keep an eye on the
ROF Online Servers list and you'll notice certain planes tend feature in more often than others, if you have those in your hangar you'll be in with the best chance of flying.
If you can't afford to buy more planes at this stage, check out the
ROF Gift Registry where you stand a chance of being gifted planes by the ROF community (if you do register there make sure you check the ROF forum for Personal Messages regularly, as most PM the gift codes).