Insulate/Vent new attic home office

My house was built in the 40s. It has a walk-up attic with a wood floor and exposed 2x6 rafters. The attic is 10' x 30'. At some point, R-19 insulation batts were installed between the rafters. There are 2 gable vents and 4 roof vents. I put in a powered gable vent w/ thermo and humid-stats a couple years ago. All has been well.

Now I'm thinking of using a 10'x10' space for a simple, low buck home office. In the attic, half the space will stay unfinished storage, the other half finished. I would build an insulated wall & access door between the spaces.

Here is a crude top view:
(ignore the ..... considers is blank space. The G=gable vent)

+--G--+...+---G--+
|........|...|..........|
|........+--+.........+------------+
|..(unfinished).......(new.office).|
|..(..storage.).......(.....here...).|
+-----------------------------+

I'm struggling with the insulating and venting in the new office area. There are two roof vents in this area. I'm thinking of removing all the rafter insulation in this area (its old), installing rafter baffling, and new R19. Then do 3/8 drywall.

I'm stuck on what to do with the two roof vents. Should I just install the baffling under the roof vents, insulate the baffling and then drywall ? Or should I make some other provisions for the two roof vents -- an access door, etc etc ?

I know the R-19 and gable venting & roof vent isn't perfect, but it is all I have to work with for now.

Thanks -

I like your graphic you made with keyboard strokes. This was pretty ingenious.

What size, span are the floor joists?

Be safe, Gary