WP, great to hear from you and I hope that you're enjoying yourself in Jakarta.
I was lugging a backpack the last time I was there a couple of decades back, so I don't have any sartorial advice. However, with regard to getting some suits made up, it may be better for you to jump across the Java Sea up to Singapore and see if you can book in with Iris Tailor or someone like that.
I know that @nabilmust has some experience with Iris, so he might be able to say more.
There's also a SE Asian version of Styleforum called "The Kerbau" (which is Malaysian for water buffalo - don't ask me why it's called that!). I think that most of the members are based in Malaysia, Singapore or Australia but you could always sign up and see whether there's anyone there who can advise on sartorial stuff in Jakarta/Indonesia.
P.S. While you're there, try to get up to the hill country so as to see Bogor and Bandung and also get down to the south coast to see Yogyakarta, plus Prambenan, Borobudur and surrounding areas.
P.P.S. Eat lots of food from streetside warungs. The murtabak is (or was) amazing.