From what you say, you have a well equipped home gym. If you don't need the inspiration of seeing other people working out around you, you probably don't need to spend time and money on a gym membership. Having said this, why not use both? When you get tired of working out at home, hit the gym and vice versa.
Presently, I am working out at home because going to the gym is temporarily less convenient. I have literally no equipment and no where to put it if I had it. This limits me to body weight exercises. It has surprised me how much I am getting out of them. Of course I am doing high reps since high resistance isn't possible. My jeans actually fit tighter in the thigh and I did not shrink them in the drier. LOL! At the conclusion of my workout, I feel pumped. The next day I am pleasantly sore. I might add some dumbbells for added movements since I'd only need a couple of sizes and they don't take up a lot of room.
I say do whatever you need to, to keep your workouts interesting and fresh. I don't need or want to get big anymore. I just want to stay in shape and this seems to be working out pretty well for me lately.
A home gym doesn't have to be elaborate like the one I have. You can do so much on a very small foot print of a gym. Look at power blocks and their bench with attachments. Also look at IronMaster dumbbells and their super bench with attachments. Just using dumbbells you can have a really great home work out. You can do something like this two or three times a week.
Dumbbell squats 2 x 10 (dumbbells held at sides and really sink it but don't bend over and deadlift it. Back straight.
Dumbbell lunges 2 x10
Stiff leg deadlifts 2 x10
pull ups 2 x max
Dumbbell row with knee on bench 2 x 10
dumbbell bench 2 x 8
incline dumbbell bench 2 x 8
dumbbell shoulder press 2 x 8
dumbbell delt laterals 2x 10
alternate bicep curl 2 x 8
two arm dumbbell tricep extension 2 x 8
dumbbell one leg calf raise 2 x 15
ab and neck
Of course there are many other exercises and if you get the attachments from Ironmaster there are a lot more exercises. You can have a really good home gym and store everything in the space of a love seat couch.