This may be a good preflop adjustment for you to make for now as it makes preflop play "simpler" while you start to get a feel for the game.
I agree with most of your post, but I tend to disagree with that statement. Calling our whole range on the BB gives us a situation where we're OOP w/o the initiative postflop, that is the worst ever scenario on the flop in Hold'em IMO. It gives you tough spots, since being OOP doesn't feel good, but folding a lot of equity to cbets feels even worse in LHE, and given Villain's superwide range (at least superwide for a NLHE player), I think playing close to optimally here requires a lot of skill and knowledge about the game, a lot more than a beginner player would have. I really don't advocate doing this, until you're pretty sure what's going on, AND you have to balance your ranges (which is rarely a case in SS 8game).
@OP: I'm not much of a NL player, so please forgive me if I say something incorrectly or something that you know, but I assume you don't.The first thing you have to understand is 3betting in LHE works quite differently than in NLHE, since you'll never ever get folds. Therefore you have to 3bet a kind of depolarized range usually (polarized only if you consider balancing your ranges). Also, the main purpose of 3betting will be to isolate a weaker range with your strong hand/range. Of course, that brings the value with it, but the main aspect of 3betting will always be isolating, getting the initiatve, and making a good flop situation for us. Therefore first in after a raise you shouldn't coldcall (except for some really special cases), but either 3bet or fold.
Now if we want to calculate ranges to 3bet with, you have to take your opponents range, and take a look at your equity against it. The important thing is that you don't have to have 50% against it, but just around 47-8% in the field, and 44-6% from SB.
That comes from the fact that there is dead money in the pot. You can calculate the exact percentages with taking what you risk and compare it to the bet you have to put in. So from the SB it will look as follows:
You have to risk: 2.5 SB (in a regular 1:2 blind structure)
The pot: 2 (openraise) + .5 (SB) + 1 (BB) = 3.5
So you risk 2.5 to win 3.5, so you have to be good in 2.5/(2.5+3.5) = 41.67% of the time. Of course take that we're OOP, the BB may coldcall or cap, the original raiser may cap, so we have to be cautious with 3betting a hand that has exactly 41.67% equity, and might just want to fold that, but we can 3bet a hell of a lot more than just hands that are ahead of his range.
From the BB the things are quite different, since you can't isolate anymore, so the important things mentioned before are not as relevant here - now the pure value comes forward, so you should 3bet hands basically if you're ahead - and you think it's a more profitable way to play them. For example with a weak offsuit A you might just want to call there, since even though you're ahead, you have SD value, and you don't want to bloat the pot OOP with a weak SD hand, since it will give you even higher reverse implied odds, etc. But the point is that from the BB you want to call hands that you'd 3bet from the SB against the same Villain.
If you know the player very well, and think he's weaktight/foldy, you also can 3bet stuff from the BB for implied fold equity, stuff like 98s, etc. where you're not really ahead, but the Villain will fold a lot on flops and turns.
I hope my post was more useful than boring, if you have any questions still, feel free.