I think your day could do with some adjusting - he has rather a lot of naps and some very short awake times for this age. Hope this isn't a silly question but is he actually asleep for an hour each time? As in, when you've said for example sleep 10, wake 11 is he actually fully asleep from 10 to 11? Or do you put him down at 10 and so he is asleep later than that with naps of about 45 mins?
Typically at this age babies would be on 2-2.5h awake time and 3 naps/2 naps and a catnap. You won't want to jump there all at once but I would start gently stretching out the awake times, extending by say 10-15 mins every 3-4 days. A typical day with 2h awake time might look like:
WU 6.30
Nap 8.30-10
Nap 12-1.30
Nap 3.30-5
BT 7
Or if your LO can do longer naps then
WU 6.30
Nap 8.30-10.30
Nap 12.30-2.30
Nap 4.30-5.15 (45 minute catnap)
BT 7
I suspect if your LO gets a bit more of an age-appropriate routine with some longer wake times you will start getting a better WU x
