Yes, but you need to confirm with them if they accept parental sponsorship. Applicants have submitted sponsorship via a parent at other embassies and told they accept employer only sponsors. I do not know the policy with Taipei. You could email them and check..
No, Taipei and Manilla have no seasoning, just submit 6 months of statements with a final balance of 500K. I got mine in Taipei, Manilla is friendlier and i was going there if i failed at Taipei.. it is a good choice.
It is E-visa only no walk applications. You can be asked for an interview after they have read through your documentation. You need to check with the embassy regarding sponsorship, some only accept employer sponsorship. If you are earning an income, why are you getting sponsorship? There is no minimum income for DTV approval, You do not have the 500K? if so better to "borrow" from dad and apply yourself
There is no seasoning requirement in Jakarta as many posts confirm You can apply with your funds. Submit 6 months of bank statements to avoid requests for more.
Majority of DTVERs do border runs, an IO also told me it is much easier and quicker to do a border run. Extending at an immigration office will require an updated bank statement with the 500k seasoned for 3 months plus paperwork to show continued activity and some offices will take a week or so to approve your application.