One month gives you lots of options to do and see lots of things!
Will you be staying in a hotel or holiday type let condo (which can work out better value and lets you do your own thing)? I am not one for long term holiday stays. ( In fact I think I have one of my own condos available in January !!)
Makati is a good bet to stay as its the central business section and close to excellent malls and the beautiful Greenbelt area with all its quality eateries.
You will want to get out of town sometime and there are world class beaches on Boracay Island which is less than 35 mins from Manila by small jet for about 100 - 150 USD return. (possibly a lot lot cheaper if you can book early ! I managed a return flight for $10 in summer! Once there its like holidaying on the Discovery Channel!
If Manila gets too busy for you and you want aquick escape you can drive an hour out of town south to Tagaytay, an extinct volcano with lake. Its high up and always 10 degrees cooler than Manila.
Manila is one place for where you don’t need to pack much at all to travel. Its always warm/hot and its best to buy clothes here they are so cheap. So save on humping bags around airports.
Donàt worry too much about “sketchy areas” you can find some gems in also in places like Malate such as “The Hobbit House” excellent cheap bar food and all the best acoustic musicians in the country will turn up there. I believe its part owned by Freddie Aguilera the top Pinoy folk singer. The name of the establishment may give a hint about the staff.
Anyway if you want to PM me I will give you any details or information I am able.
I am going back to Manila next week on rotation for three weeks returning here to Italia Jan 7th.
Could maybe meet up for a San Mig! Oh by the way the Balut is actually fertised duck embryo not chicken. You can buy them at 7 days old 12 days old or 21 days old ( at which stage they are practically kicking their way out of the shell!