I'm currently riding 7 days a week with my goal being to improve my speed and to complete a ~95 mile ride in under 5 hours in November. I finished the same ride last November in about 5:10, so I don't think I should have too much trouble. My schedule looks like this:

Mon: Recovery ride (~10 miles at roughly 10 mph).
Tue: Roughly 2x15 intervals (around 35 mins with 2 ~15 min 175+ bpm efforts - ~12 miles).
Wed: Same as Tue.
Thu: Same Tue.
Fri: Recovery ride (either same as Monday or riding around on the BMX for ~5 miles and using most of my energy to hop over stuff, off-road, etc).
Sat: Currently 42 miles @ ~160 bpm average
Sun: Same as Sat.

My questions are:
1. Would I be better off spreading out the recovery days? Maybe move the Fri to Thu?
2. I'm currently maintaining an average HR of 160 on the longer (42 mi) days. Should I be paying less attention to HR and focus more on riding further? I know I can ride much further, but it seems more challenging to do the 42 miles and maintain a relatively high HR.
3. I ride my recovery rides at low cadence (~60 RPM) and quite slow. I don't feel any stress in my legs at all during the recovery rides, but would it be preferable to ride at a higher cadence as long as I can keep my HR down? I usually try to keep it below 120 bpm on recovery rides. I feel that having a recovery ride day is more beneficial than a day off, anyone disagree?
4. I've kept the distance of my daily rides to ~12 mi and focussed on completing them faster rather than increasing distance. This is mainly so they don't occupy too much of my time on the weekdays. I can probably ride for up to an hour on weekdays though. Should I see significant gains by increasing mileage on weekdays?