yeah i think its enough. doing too much can be a reason for both overtraining and that you dont feel it is fun, it becomes a chore...
personally i would probably rather do triceps with back and biceps with shoulders since doing biceps after back, theyre allready worked a lot, maybe even pumped, after back... and not as fresh as i would like them.
dont know how long you are in the gym and if this is a problem. ive been on a program before when i was in the gym for max 30 minutes, it can be done especially when only doing one body part...