Yes, flying via MNL is a great way to save money while experiencing the comfort of J.
I've done this using PR - a couple of overnights at a MNL hotel - then WY (Oman Air) to LHR, returning from one of five European ports to MNL, then overnight stay or longer, PR to MEL/SYD. PR and WY use T1 at Manila NAIA: EY uses T3. T1 is a great improvement on the atrocious T2 that PR international flights used until a few months ago. (PR domestic flights use T2 now).
J fares to UK/Europe consistently seem cheaper from MNL than from BKK, CGK or KUL. With WY, theY cabin is almost always full from/to MNL but in J, my experience on WY is there's been 10-14 pax in J, so not all seats taken. WY has excellent 'dine and demand'.
I always have the flights Oz-MNL-Oz and MNL-LHR-surface-Europe-MNL on separate PNRs. Apparently combining dramatically increases the return J fare.
The food presentation on EY in J doesn't look great, but I may (re)try EY from MNL if the price is right. I will take others' advice and try to avoid the flights with B777s.
MNL's typhoon season is c.June to December so if flying at these times, I endeavour to have two nights each way in MNL as a precaution. Airport hotels near T1 or T3 at NAIA such as Belmont, Holiday Inn Express (previously terrible Remington but apparently better now), Kingsford and Savoy can be as little as A$80 a night for a Queen room without breakfast. Okada Casino has excellent buffer dinners and lunches and is close to Kingsford Hotel. Mall of Asia is not far away: best to visit in the morning or early afternoon rather than early evening as latter has 'traffic' (congestion).
Provided you use a regular white 'street' taxi and not the white 'coupon taxis' or yellow 'airport taxis', MNL's taxis are super cheap. I usually tip the driver but most times it isn't expected. If a driver quotes an outrageous fare, walk away, or if in the taxi, say you want to alight. That will usually solve the discussion.