Well first I want to applaud you for taking the initiative to start working out despite some limitations. What you're doing is not bad by any means, so don't let anyone tell you differently. You're doing something consistently which is great, but I think you could do it more efficiently.
Personally, if there were 2 lifts I would not want to sacrifice, it would be squats and deadlifts. Ideally, you would have a power rack, (olympic) barbell and plates, and a bench. That would enable you to do the primary compound movements. I have a half rack thing from Dick's that was a little more than $200, and got an olympic barbell and plates from Craigslist for $180. There are alternatives for now. If you look at exrx.com, there will be exercises you can do using the equipment you have already. Also, as was already suggested there's bodyweight routines too. BUT, if you want to bulk and add mass then it's really going to be best to be able to do the compounds where you can move the most weight.
As far as your current routine, it seems to be more in line with bodybuilding, as in prioritizing hypertrophy and aesthetics. That's based on the rep range you're using. I personally have been doing a 3x5 program which prioritizes strength, but will incidentally cause hypertrophy too. In a little more than 2 months my lifts have increased like crazy and I've gained about 12 pounds. But again, there are alternatives. While I'm more in the camp that wants to build a strength foundation to maximize hypertrophy work, there are people who will go straight for the hypertrophy using higher reps and volumes like you have been. As long as you're able to progressively overload, that's progress. There's a few other things I won't address yet since this is already a lot of text, but feel free to ask anything.
Your assessment for diet sounds pretty accurate to me, but if you haven't then definitely calculate your TDEE. I'm 5'8 and started at 150, and have been eating 3000+ daily, but I know that's well above what is necessary. I basically went from light cardio to no cardio wanting to really maximize the bulk, but I'm going to be adding in cardio again now. I just think of it in terms of calories, so for you I would just want to be sure that whatever cardio you do isn't putting you below your intake goal.