Promote/demote entry only on chosen category(s)

I would like this featured to be implemented: It's really important!

A few examples scenario:

1)users can post an entry for 30 days for free basic listing (with 0 credit package)

2)Admin can set up another promoted package let say offer 3 days, 7 days, or 14 days to promote an entry (with e.g 15, 25 or 50 credits) Then when the promoted entry expired for given days, poster can choose to re-promote the entry or otherwise the expired entry will be demoted to basic free listing instead of completed expired.

3)The promoted entries will be sticked on top of chosen category only. Ideal to allow user post on multiple categories, where credits will be deducted accordingly set up for multiple categories.

Please note: Promoted entry on frontpage is not the best way, since most users e.g looking for Jobs ads, or used vehicles they won't be looking at frontpage. They will go to specific categories rather than looking frontend. Therefore the advertisers would see the benefits of promoting their entries on specific categories. I don't see why should I promote entry for selling Fridge, while if buyers search for 'Fridge' in 'Fridge & Freezer' category my entry won't show up on top of that category. Instead will show on frontpage where it's just transit page.