Hey up Jake
Fortunately playing the pipes is definitely more rewarding than posting on the forums here. Shame you're not in the middle of England I'd try and recruit you for a regular session
As a former GBH player myself I used to hate that left out feeling I got when other folk got the session on. It was only ever in the really loud pub sessions that I used to get to play. Despite my new border pipe I do still get other instrument jealousy though. Being able to adjust your volume and drop in and out of a tune at will, as well as being able to stop between notes definitely makes the difference between a jamming instrument and a bagpipe, at least it does when you play like me.
As a GHB player, regardless of what some might say, I reckon you've got a better chance with the fingering and demands of the instrument than those who haven't had that background. There's still however a horribly limiting/wonderfully defining edge to the tonality of a smallpipe that means that the largest part of the session players you encounter (outside of the truely "Celtic" bars) will completely fail to understand what you are doing even if they are playing trad music. If you are anything like me the fact that your entire musical education has come from a wierdly pitched modal instrument will mean you are ill equipped to tell them what it is they are doing wrong also!
Sadly, although wonderfully authentic, a lot of the music promoted for session play on the smallpipes will be met by complete indifference by the people you are most likely to encounter playing in a session. If you can try and move away from GHB pipe tunes and settings of the music for the most easily transcribed session tunes you will certainly feel more a part of it if this is the aim. After that it's a question of being able to play what they are or dragging them with you, the latter being certainly the happiest of solutions.
Whatever your choice and however you do it I hope it's fun and I welcome you not as an official representative of this site (which I most certainly am not) but as a fellow frustrated GHB player looking for greater musical freedom. Onwards and upwards....