[Q] AOSP ROM and S-pen topic

I'm looking for a tablet for note-taking on PDF files in class/meetings.

I found Surface Pro is perfect for that but I'm an android guy using gmail/hangouts all the time. Someone suggested Note 10.1 but I prefer AOSP. I have several questions.

1. If I install custom ROM, can I use S-pen for regular apps with palm detection? (Note-taking on PDF is my main objective)
2. If I use stock TW ROM, can I remove Samsung Gallary app? It is not compatible with my DLNA devices.