You already mentioned some of the points.
I guess you are talking about shorthanded tables.
-You should be less inclindes to 3bet OOP because your 3bets will get called more often.
-Your speculative hands are more valuable because in general your implied odds are higher, but:
- it is important to not overestimate your implied odds! Base your decisions on facts, don't start with thinking processes like:"i just get 1.5:1 odds on my 8 straightouts, but hey we are deep i most certainly have huge implied odds - i call"!
- At the same time most hands like AQ/AJ that are likely to make a good top pair are less valuable since you have to go for potcontrol more often.
-Your BRM should definitely be somewhat more conservative.
But since you mentioned you are still playing with a SHC my advice for you would be to slowly approach the deepstack- tables by slowly increasing the amount you are buying in with.
Start with 120BB, play a few thousand hands and then try 140BB and so on.