Simplified summary:

"Trail" is the factor that most influences handling, and as noted above, trail is determined by the interplay of head angle and fork rake.

Head and seat angle and top tube length determine rider placement on the frame and weight distribution between saddle and handlebars.

Chain stay length determines wheel clearance, overall wheelbase, and also clearance for cargo panniers.

Taken together, the frame is a system where no one measure can be changed without influencing others, and what might be best for a particular rider depends on their body, riding style, and expectations.