Transferring internally within the same trust/hospital is usually somewhat quicker/easier than applying somewhere external, you do normally still have to go through the process of applying on NHS Jobs and being interviewed etc., but then they don't have to repeat all the ID, reference, DBS, health checks etc as your personal file just transfers over so that bit is quicker, plus sometimes (but not always) they'll agree to shorten your notice period if it's an internal transfer.
If you apply to another hospital or different NHS organisation, or a GP surgery, it won't really be any quicker for you than any other applicant I'm afraid and you will usually have to give full notice. Bear in mind also that with GP surgeries, unlike hospitals, they don't have to comply with Agenda for Change, they can set their own pay rates and terms, and they won't necessarily match your NHS salary if you are already halfway up your banding (they may do, but if they can employ someone cheaper they often will). Do read through your contract carefully if you do go down the GP route as it can take people by surprise that they don't get the same holidays, sick pay, mat pay etc as they assume because it's NHS it will be the same but it isn't always (at all)...
I work in HR so can't give you direct experience but I would say being an HCA in GP or outpatients is quite a different experience to on a ward. I won't say one is easier or better than the other, there are pros and cons, but the HCA work in clinics seems more routine, you'll usually have your set tasks that you go through (whether that's taking measurements/obs, doing bloods or blood pressure, clerking patients in etc) whereas I guess on the wards things seem to be more varied on a day to day basis. On the wards you probably have more of a chance to build a connection with the patients as you look after the same people over a period of time, whereas in clinic it seems more 'thank you, next' although I guess in the community you may see the same patients more regularly and build up more of a rapport.
Obviously most outpatients and GPs work on largely office hours which may be a pro or a con for you, easier for childcare etc but no unsocial hours enhancements so again even if you are on the same banding point your take home pay will go down compared to if you were doing nights etc before. If you need flexible working or certain shifts it may or may not be easier to arrange this compared to being on a ward, in GP practices particularly larger ones some of the HCAs seem to work mornings or afternoons only which might suit (although wherever you work morning shifts always always seem to be the most in demand!).
I do think it's quite a different culture working in GP than hospitals, different pace of working, smaller and more tight knit teams which again may be a positive or negative depending on your personality type!