To be honest, it is quite expensive to go to agency when you can do things yourself. I agree with Rayna about using the money for the wedding or visa application instead.
You should consider these options:
Option 1. a. Get married in Phils
b. Apply for Leave to Remain straight away
Option 2. a. Apply for FLR M
b. Get married in the UK within 6 months
c. Apply for Leave to Remain
Good luck Mcgregor03 with whatever path you take. And welcome to the forum
