I think radio calls in an uncontrolled circuit should always include the runway being used and the circuit direction being used.
Agree. And I've been in a situation once or twice where I flew a right hand circuit where a left hand circuit was standard (due to circumstances) and I actually called "right repeat right downwind 27" to stress that I'm not where others might be expecting me.
Not good practice of course to use the opposite circuit but there are situations where it's the most sensible thing to do. (Empty circuit, big shower on the live side and permission from ATC was one.)
G-XXXX is rolling runway x, intending right turn out or whatever.
I always find a call like this amusing. Since "Tenerife" we've all been brainwashed that ATC uses the term "take-off" first, and will only use that term in the context of your take-off clearance. Up until that time the term to use is "departure".
But the result of this is that pilots are actually afraid of calling their take-off a "take-off" at an uncontrolled airfield, where there is no ATC to issue a take-off clearance.
I haven't checked CAP413 but why can't we simply call "G-XXXX is taking off runway x?" at an uncontrolled (A/G or AFIS) field? That's what we're doing after all.
The only time I'm using a call "G-XXXX rolling" is in the following situation:
"G-XXXX you are cleared take-off runway x, mind wake turbulence from the preceding 747"
"Cleared take-off runway x, two minutes for the wake, G-XXXX"
"G-XXXX roger"
(two minutes later)
"G-XXXX rolling"