What do you guys think about 2x T9 + 2x T10 for blood dps? (Sounds good to me, very good bonuses from both T9 and T10, T10 4 set bonus is not great but the 2 set bonus is important, extra tip: The tailoring profession-only swordguard embroidary
https://wowwiki.fandom.com/wiki/Swordguard_Embroidery is amaaazing! It procs around every one minute. Combine the embroidary proc with hysteria, dancing rune weapon, and trinkets, you're going to do burst damage!)
What trinkets should i use? (I use Deathbringer's will and Mark of Supremacy, you can replace Mark of Supremacy with any other trinket like Sharpened Twilight scale for raids. If you pvp, then you can replace it with Corroded Skeleton Key or any other trinket you need based on the situation, When I started using deathbringer's will, I noticed a 1k increase in DPS - quite significant)
Arp is the best stat? (yes. My dps doubled when I went from 30% arp to 100% Arp. So yes, Arp is very very very important because your highest damage dealing abilities are pure melee, and not magic. If you have the talent blood gorged, you will automatically get 10% arp, thus you only have to stack up to 85-90% arp, if you don't have much arp gear - gem on arp. The more arp u have the better it is, but it only really starts to become good after 70%)
What spec should i use (link please) ? (This is what I use at the moment
https://imgur.com/a/l5NvOps BUT you can change based on situation! Don't blindly use it, try variations of it. I put two points in Night of the Dead - because I like to rely on myself for healing and if I can get a ghoul, I can heal myself more often in emergencies, also the ghoul does a lot of damage, a lot, that's why I reduce it's cooldown. But anyway, this is an optional talent. You can put those points elsewhere too. This is a PvE spec that suits me.)
Any bis list for that kind of gear? (Sorry, not sure, but someone linked it above - currently I use all Arp gear - my GS is about 5.7k and I do above 8-9k dps on a dummy).
What weapon should i get ( no shadowmourne) ? ( I use
http://wotlk.cavernoftime.com/item=50798 Ramaladni's blade of culling because of the armor penetration stat. And because it has two sockets and expertise - I am low on expertise so I need to make it up. If you are Arp and expertise capped, choose another weapon, if you have 25 primos and the bloods of Festergut and Rotface, you can get Shadow's Edge too. Tbh most weapons will work, use based on the stats you are missing. Just make sure it's a two handed slow (roughly 3.5) weapon).
Direct message me if you have questions.