Reavers.....well at first I thought to myself that I would never be seeing them used again.....until I saw their points drop. Okay, so we have lost the D3 hits when we turbo boost, but it's not all bad. Something else I haven't seen talked about is the increase in unit size from ten to twelve. Not huge? Well actually it is. It means that early game panic checks won't occur until you kill at least four. Plus it always helps to have a lot more attacks. It also means you can have FOUR blasters/heat lances in the unit now....which is AWESOME. PLUS, the new power from pain rules benefits these guys the most. In all honesty, I would always reserve these guys, or at least keep them far at the back - unless I needed them of course. Wait until they boost up to have FNP, and then just launch them forward. A unit of twelve isn't hugely expensive, in fact you are looking at about 250 points for a beefed up unit of twelve.
Scourges......are pretty damn awesome. Absolutely nothing has changed.........except getting a 6 point drop per model! You really can't leave home without some of these guys now. They really pump out a lot of damage for their relative points cost. Plus you can outfit them however you want. Two ways I can see them being used....Firstly as fast moving Blaster platform to just take out vehicles. Alternatively, highly maneuverable Splinter Cannons. They are comparably tougher than trueborn too.
The court of the Archon is interesting to say the least. The points drops are appreciated, but I am still not sure about this choice. I do like Sslyth's though. They were overpriced, in my opinion, before. However, now they may see some use. T5 with a sharcarbine is pretty good, and considering now that Splinter Racks is now for ALL splinter weapon, it is definitely something worth considering. I wouldn't take 10 of them in a raider, but 3-4 in a raider, with a medusa thrown in isn't too bad a choice. However, I guarantee it will be the first target from your enemy once they realise how many re rolling splinter shots you are getting....The other thing to consider is a Portalling squad of medusa's....No scatter is hugely beneficial for putting a bunch of ap3 templates into play - except vs Tau of course....but you are screwed vs Tau anyway!
I think if you look past the changes to the codexes "cool" factor, you can really see that the designers were going for a fast paced type of force.