My region is fairly flat by the sea. We have a lot of cycle paths.
I will use the bike a lot in town.
Here are my doubts
EFFECTIVE TOP TUBE
Should I lengthen my effective top tube (and reach) ?
I plan to put a 110 mm stem

DIRECTION ANGLE
My understanding of the steering angle is that the more the angle is closed, the more stable the bike is at high speed. a more open angle means more responsive.

SEAT ANGLE
On most of the bikes I have seen, the angle of the seat tube is equal to or slightly less than that of the steering angle.
What insidance on the geometry of the bike? more closed means further back and a more raised position. this also has an impact on the chain line. Do you have an opinion on the subject ?

CHAIN LINE
I like the idea of a very short chain line to be able to accommodate the rear wheel in the seat tube and give it a more aero line.
I also like a short chain line for more responsiveness. but are there any other parameters to consider?