I personally like these sectors better than the rest myself.
You can get a plot for 45 in E sector and F1 (there's no 'F'). Although the plots in this range would be in some sort of disadvantage e.g. Khadda, depression, backfill etc. If you can extend your budget to 50 you should be able to comfortably get a decent plot there.
Do keep in mind that E sector's middle/back is better than the front. It's revered in F1 - front is better than the back. I'm talking height wise and fill wise.
And I don't think prices are declining any further much. So much so that you can get your hands on a decent plot now instead of waiting for the desperate sellers to dispose of their plots to greedy dealers (I'm also part of the wider community).
Maybe we can strike a one-to-one deal on E sector's 98 number plot, which is a boulevard plot and owner is asking for 54 lacs!!