you need concentrated stress - and because you're so limited in terms of full-body, systemically-taxing exercises, you have more room to play. volume and variation will drive size pretty well. i would suggest something like this:
core work daily - alternate heavier/higher volume w lighter/lower volume
split upper body into pushing and pulling.
day 1 - pushing focus
day 2 - pulling focus
on the focus day, most of your work will be for that type of work. you will still do the other, but w less volume/intensity.
for each "cycle", choose 1 primary exercise for each - this will be your big, compound lift that you will use as the real strength builder. for pushing, this is bench, incline bench, press; for pulling, this is row and pull-up.
on the focus day, do your big exercise first. several sets of relatively low reps, i.e. 5-8 sets of 3-6 reps. strength primarily but also some hypertrophy. this exercise you stick with for a few to several weeks pushing the weights up.
then throw in some accessory work at higher reps/total volume. this is dumbbell/KB stuff, calisthenics, etc - 3-6 sets of 10-15 reps/exercise, maybe 2-4 exercises. These exercises you change each workout for variety.
finally finish w some accessory work for the non-focus movement, but only 1-2 exercises, 2-3 sets each, and push it less than you would on its focus day.
i would ramp up the total volume of the accessory work gradually so you continue getting a push from the volume as well as everything else.