Early-bird Discounts - Different rates, same event

I often use the early-bird discount feature on my events. However, I keep running into the situation where I need to have different early-bird discounts for different configurations within the same event. Early-bird at this point is just one global discount.

Example #1 of what I often need:
>>> Standard Individual Registration: $55/person discount
>>> Student Individual Registration: no discount
>>> Group Registration: $50/person
-- for the "Student" registration, I usually set up a negative-value fee-field radio group or drop down menu so that registrants can select this as an option

Example #2 of what I often need:
>>> Standard Individual Registration: $25/person discount
>>> Group Registration: no discount

In the case of the Ex#1 - Student rate and the Ex#1 & #2 group rates, I've got around this before by (1) changing values on the custom fields, or by (2) adding an additional conditional fee field that adds the early-bird discount back on, but in both cases I need to manually remove or modify these workaround once the early-bird deadline passes, otherwise the customer is paying either less (workaround 1) or more (workaround 2) when I'm not able to manually remove these workaround until I'm in the office 9 hours after early-bird expires.
I would like to somehow remove this manual step and the extra work / payment issues it causes. My registrants are all (hopefully!?!?) honest, so I could just forgo the built-in early-bird discount all together and just include a fee field checkbox that adds a fee on "if registering after the posted-somewhere-else early-bird deadline" (I don't want to have to set up a separate field for EVERY event listing the deadline every time if I can avoid it).

Does anyone have any suggestions on a better way of doing this? Is there any way to pull the early-bird deadline (or some sort of 'early bird discount being applied' status) via javascript / jquery / php and use that information in a custom field (eg. code inserted into the field text boxes)?

Would it be a conceivable feature request to add different early-bird discounts for individual and groups? (That would fix my group rate issue).
Is there some way that early-bird discounts could be adjusted by custom fields? eg: an additional box in field editing, similar to the existing 'fees' box, that would allow different early-bird discounts to be entered. A second box could be added for late fees too.

Does anyone else need this level of control added as a feature?

@Tuan:
Would the following idea be practical to implement, and how much would it cost to add. Do you feel that it might be something that could also be used in the core release after it is developed?

Idea: provide a way to link [Early Bird Discount Date] (and new additional date) to used-selected [Custom Fields].
Problems solved with this: Ability to control fields by date. In addition, also adds possible support for a way to do Late Fees.


This could be placed under the Advanced Settings tab instead as the Additional Trigger Date could be used for purposes other than "discounts".
If not included in future core, roughly how much code would have to be maintained by me (I can see changes needed to Admin -> Events, and Registrant -> Group and Individual forms; items in the cart might also have to have some sort of expiry flag attached to them in the case that a carted item is not checked out before one of the dates pass which could change the fields available to that event; Don't know how this would impact front-end event creation.)