Hmm ok, perhaps here's something to get you started.
For every piece you have, calculate how much it is worth in terms of PP
To do this here are some guidelines:
1 hit rating = 1.88 PP (if you are over the hit cap, then 1 hit rating is worth 0 PP)
1 sp = 1 PP
1 haste = 0.98 PP
1 Crit = 0.76 PP
1 Spirit = 0.59 PP
1 Intellect = 0.22 PP
1 Resilience = 0 PP (obviously)
Source from
http://www.shadowpriest.com/viewtopic.php?f=62&t=24134
Now calculate the PP value for every single piece of your gear (except for trinkets) and determine which pieces have the lowest PP value, those are the pieces that you will need to replace first. For example your Strip of Remorse is worth 245.52 PP whereas your Wrathful Gladiator's Pendant of Subjugation is only worth 174.92 PP.
It doesn't matter if you drop haste (for crit) or not, you should aim to get a higher PP value on your gear. If a piece of gear gives no haste but it gives a huge crit boost that will give a higher PP weighting than your current piece then by all means change to the crit piece.
Also save up your Frost badges and get Tier 10 Shadow pieces.