While your idea would be nice for the playerbase, I doubt cryptic is going to change it. It's a a simple mechanic to force or rather lure people into logging in on a daily basis.
Uhm actually no, that's a bad idea.
Why would it be a bad idea from a players perspective? If you want to keep it the way it is, just set the slider to 20 hours, while people who'd like longer projects could just set it to 40, 50 or 60.... How would it negatively effect you if other people had the choice to run 40-hour projects, while you could still run your 20-hour ones?
Uhm actually no, that's a bad idea. It's bad enough we have to wait 20 hours but to wait longer per project means waiting longer to get the better gear.
How would it be a bad idea to give the player (at least something of) a choice of duration of a rep project? It's a good idea, and gives each player the ability to slot a rep project of a length that's suitable and convenient for them, that fits their real life commitments.
If I'm grinding out some rep and I know I'm going to be away for, say, a week without access to the game, I would like to be able to slot a week-long project, with appropriately raised marks and consumables requirements (and payout), rather than just a 20 hour one and waste those 6 days, which then means I have to wait 6 days longer to get to top tier.
Away for x amount of time? Slot a project of x length. No time wasted, nice and efficient.
The length of the projects makes no difference, it's the efficiency of when you slot them, which is where projects of different lengths would be very useful.
Allow players to set the duration of a project themselves, and adjust the rewards and requirements accordingly. 20h Project gives 100% rewards (as it is today), while adjusting it to 40h, gives you 200% rewards (the same as completing 2 x 20h projects), while you could also adjust it to 10h for 50% rewards (half of current).
Why would this not be possible? How could it be exploited, if the rewards and requirements are reduced at the same time as the project duration?
I like the idea - coding may prove to be difficult, if the current is hard coded.
I think there would need to be a cap though, max of 5 days duration (or some other number, but not too high) of course the cap would have to be no longer than that one project giving one tier upgrade. Think about it - I'll open a project at T1 and extend the project as long as it would take to get to T5 - therefore only costing my T1 prices... yeah not going to happen - for many, very good, reasons.
However, capping the max duration time to whatever the needed XP to the next tier wouldn't be too bad of an idea....
Why are the personal rep projects capped at 20 hours? Why can't the timer be adjusted & adjust the requirements needed for the extended time?
When the reputation system was first introduced, the long cool-down timers caused everyone to rage. As a result of the long waiting periods, Cryptic rightfully reduced the timers from two days to one day. People were walking away from the game.
Second, once a reputation system project is completed, the system does not suddenly erase your progress. Regardless about when you sign on, the reputation project you set into motion will be completed. You will never-ever lose your progress, nor will the reputation system suddenly shutdown.
Cryptic should reduce the cool-down timers, for the twenty hour waiting period is too long. I have halted my alt's progress at T3, for I got tired of grinding and waiting.