Hi there
It's a bit hard to tell from your EASY just how long the A times are right now. If it's 7.30am-10.30, 3hrs then that ought to be enough to give some good naps really. But if it's 7.30 - 10.00, 2.5hrs then this is perhaps too short for a 6.5 month old.
You said you were running on set naps, how about just shifting the set nap 15 mins later (set naps do change times just not daily, when the A time needs extending you move the set nap time)?
So something like:
WU 7.30
A 2hr 45
S 10.15 - 11.45
A 2hr 45
S 2.30 - 4.00
A 2hr 30
BT 7.30
Looking at your times though, seems your LO might have something like a 37 min sleep cycle which may be giving 2 cycles in that 1hr 15min nap, so you could be looking then at 3 cycles making a close to that 1hr 45 length nap you mentioned. That sounds like a restorative nap, I'd aim for that if you can.
FWIW mine always woke every evening, making noise, stretching noises, grumbling, crying, all sorts of noises in the evening hours. It happened pretty much every night regardless of how great his routine was, there was just no stopping it, he is just a noisy sleeper. Often not settling into a real proper sleep until midnight. Tiring for me but honestly you can try every kind of OT/UT routine change and not stop it if he is just a restless sleeper like mine.
You do have a lot going on right now, you know that, so I'd go for the time tweak but keep expectations low.
I'd suggest moving the solids meal to earlier in the day, an hour after the WU milk or an hour after the mid morning milk is a good time to try solids. LOs tend to be more interested in food earlier in the day but also there is less chance of wind or digestion disturbing sleep if it's earlier in the day (any adverse reactions you have all day to notice and sort out too rather than it being in the night).
hope this helps