If anyone hadn't figured it out, me and BKC have almost identical favorites. We do have polar opposite views on some things (Bulky Starmie is a frail piece of shit to me despite him loving it) but a team that gels well with one of us will generally be comfortable for the other. As you'd expect I also have a preference for sand stall.
If you want a good background to understand what I'm saying,
this article on how to mix and match your resources is a good start. This is basically the intuition I use to teambuild exported to text after I've recieved inspiration for a team. It doesn't necessarily have to be stall, just any team that intends to take hits before it achieves its goal.
There is intuition not included in that article that is still very important to me, building ev spreads. It's not there because I'd literally have to make graphs for every defensive pokemon, but I think it's a key concept to understand when you are getting diminishing returns out of EVing a certain stat. With Blissey, you never want to use a huge amount of HP EVs because once you get past 100 or so there's almost never a defense for not putting them in special defense instead, where you actually get a solid return. With Forry / Tangrowth, I would almost never go above 136 defense EVs because the 120 EVs in spD are the difference when it comes to Ice Beams / Hydro Pumps respectively. I actually recently got to take an extra move vs Kyurem-B because the defensive balance helped, and I've never lost a turn vs Terrakion / Chomp etc. because of it. Look at the 3 defensive stats of the pokemon you are EVing, and if one is low compared to the other try to find an insignificant stat to steal just a few EVs from, they will go a long way. Even on a mon that is generally only supposed to wall one side, I encourage you to do this and discover it's benefits.
I would like to point out that calling these teams "Sand stall" can be misleading. "Sand stall" operates as just weatherless stall that doesn't want an unfair disadvantage against Rain / Sun or in past gens stall that wanted either Ttar or Hippowdon. I hate little more than when someone says "weatherless stall/offense is so underrated" because it operates no differently than "sand stall/offense", all that's doing is just avoiding running Sand because you want more of a "challenge". It's like saying your "no nature boost" team is innovative just because it leaves an essential competitive edge on the side for a gain as relatively significant as strengthening your Blissey's Double-Edge.
While remembering to refine every detail you can, play as much as possible while trying to involve the tips from my article and discovering your own. Most people need to pile experience with sand stall to get comfortable with it, even more so than normal pokemon.
Regenerator mons are the shit in BW. Getting comfortable with a Tang / Bro / Amoon really gives you flexibitity against offense and choiced mons, spreading status while scouting their moves. It really helps against residual damage from other stall too while you try to wear them down with support moves.
Scarfers are also super useful, glass cannon offense is the norm, meaning you can often break randomly put together ladder teams with one coverage move and / or just keep yourself in the game more easily against one that has proper synergy.
As a final note that didn't fit well elsewhere, run 0 speed on your Forry. This goes back even before pivoting out with Volt Switch into your glass cannon, in any gen you need it to be slower against other Forry. This helps you as you spin after the other one sets up and lets you win a one on one PP war. If you are faster, it sets up after you spin that turn and can then block / stall you out of PP if it wants to.
