As a former Chief Clerk I served six Adjutants in four years. They exist to bully Subalterns in the Mess and sign whatever the Chief Clerk tells them to sign. Other than drafting visit programmes, it is difficult to see the point of an adjutant.
You do whatever the CO deems necessary, from making the brews, keeping his diary, briefing his driver, organising VIP visits, drafting and proof reading letters and documents, coordinating disciplinary action at Unit level and, above all else, you guard the CO's MS flank. There is more, much more, this little lot is just off the top of my head. It's not what I would describe as a fun job, but you will learn a tremendous amount about command and administration.
As a former Adjt, I served with 2 Chief Clerks over 2 years and have had to suffer one or two utter twats at staff. To be fair, at RD they were bloody good chaps (but that was before AGC). The role of the Chief Clerk is to help bluff the CO that the Adjt's a damn fine chap and should be a CO one day himself. Other than that, and I suppose being friendly with the beastly RSM, difficult to see the point.
In smart, or, even, pretentious regiments the Adjutant glides serenely about his domain immaculately dressed in breeches and highly polished riding boots. As he negotiates his way around barracks doors magically open before him, litter disappears, soldiers stand (to attention) in awe, subalterns gulp apprehensively adjusting their uniforms, the Pipe Major often seeks his advice on the finer points of Pibroch, Company Sergeant Majors smile benignly as they remember his father when he commanded the Battalion, the Regimental Sergeant Major defers, diplomatically, to him often sharing a conspiratorial smile.
He is comfortable around the Commanding Officer, treats the Second in Command as an equal, defers to Company Commanders he thinks may eventually command the Battalion and chivvies along the Chief Clerk and his motley crew of shiny bums. If he is very lucky he will have an LE Assistant Adjutant (whom he treats with condescending politeness) who will do all his staff work giving him ample time to hunt and shoot.
Go for it - you'll be liking it...umm....mate!
I work for 2 x Adjt's during my tenure and actually they were decent blokes. Fair play to back at RD, is bang on. The Adjts job is a important one, you are deffo the CO's RH man and CO's will also look to you for advice as they wont be up to speed on MS matters. But ensure you look at your SSA's as they can have a wealth of knowledge - if they have qualified in the job. That's the problem in many Regiments though they don't have the SSA qualified for the job, which is a nightmare.