Looking for a few claws build suggestions

I am wanting to know based on the end game incarnate stuff which secondary can get the most out of claws. Or give the most to make claws better. Essentially what I want to do is build a character based on 2 possible things. I wanted to put the chance for build up proc into follow up and focus in hopes I can keep them up alot of the time. And I want to try to have the best possible slotting for follow up. So any build suggestions for this? and any incarnate slot suggestions. My highest claws (claws/wp) character is 25 right now and tried the chance for build up proc and its really nice. I was thinking of procing out slash too but i am not sure if its worth it or not. I guess in a sense I am looking for opinions from players who have already done something similar with claws. I am willing to start a fresh alt for this since leveling takes no time now.

I had a claw/sr but has since been retired (dm/sd is just too fun)

As for all of your questions it really depends on what you are wanting
IIRC (please correct me if I'm wrong) the best DPS chains for claws are:
Follow Up>Focus>Slash
(I think there is another here)
Follow Up>Focus>Slash>Strike

If you are looking to get to that top chain /Sr and quickness will help you out but with the new trials /Sr is looking less and less awesome (but somebody feel free to correct me about /Sr's performance in the trials)

In my opinion Claws can pretty much be paired with anything and rock your socks off (except maybe regen with the redraw) so it comes down to more of what would you enjoy playing and how much you are willing to invest in it. Invuln and WP are solid choices and with the right amount of inf pretty much anything can be made to survive.

As for incarnate slots I would say you would have to find out what power sets you would like to take and then build around that to fill your weaknesses.

For Slash 5 Crushing Impacts for the Rech bonus and the Achilles' Heel Proc seem to be pretty standard slotting (at least on an /Sr), but for any secondary its a nice place for that proc.

For Follow Up, its a good attack and buffs your dmg so you pretty much want to max out its dmg/rech/acc (I might not recommend the build up proc as its only a 5% chance for a tiny burst but if you like it then keep it)

For Focus in a thread awhile back when I was building my claw/sr I had an extra slot in focus for a proc after 5 pieces of Armageddon (all but dmg) and Werner did his maths and told me that I would get more mileage from slotting the Explosive Strike Dmg Proc (IIRC)

Hope this helps!