I am a 31 yr old male and a regular in the gym

and have been for some time. I have tried several routines over the years including different eating plans in the quest to pick up size and have had some success (but not as much as I would like). I am somewhat of a hard gainer

so certain things work for me and others do not. My current training routine is as follows:
Mon: Shoulders and Calves
Tues: Chest and Abs
Wen: Legs, Quads and Hamstrings
Thurs: Arms, Bie and Tri and Abs
Friday: Back, Forearms and calves
I currently do 3 to 4 exercises depending on the muscle group with 4 sets + 1 warm up. I have cut down on the weight I push to increase reps and the pump in muscle, I found recently regardless of weight I was not achieving a good muscle pump anymore.
I include cardio almost every day

, either a 20 minute run or cycle depending on what I'm training; I prefer a cycle if I am training Legs or Back as I find my energy levels are pretty drained after those muscle groups. I firmly believe in the statement "you are what you eat" so I do my best to eat pretty clean and regularly.
Anyway, I am always interested in listening to other people’s opinions and ideas and am willing to share a few of my own, if anyone is interested.
Cheers