OP, here are some more random suggestions for you:
1. For 77,88,99,TT,JJ,QQ calculate or Google the following:
a. The probability of flopping an overpair
b. The probability of flopping one overcard
c. The probability of flopping a set
d. Your hot/cold equity vs. various number of villains and ranges, i.e. 1 20% range and 2 60% ranges, or 4 70% ranges etc. Pokerstove can help with this.
e. The % of hands that have your hand crushed (higher pocket pairs) or are only a small dog against you (overcards).
2. When you do flop one overcard, calculate/estimate the probability that at least one of the villains paired it when you have 1, 2, 3 or 4 villains (this can be challenging because the villains don't necessarily have completely random hands - you can start with random hands to simplify the calculation and then adjust from there).
Random thought: With ANY hand preflop, pocket pair or otherwise, it can be useful to ask yourself the following questions:
1. What am I hoping to flop?
2. What is the probability of actually flopping it?
3. If I DO flop it, what is the (approximate) probability that either it will be the best hand at showdown or I can blow everyone else out of the pot? (Note that this depends on how many other villains see the flop, which can affect your decision to limp, raise, coldcall or reraise)
4. What am I going to do on the flop if I get a non-ideal flop? (This one can have a lot of permutations, i.e. are you in position, out of position, 1 villain, 5 villains, size of the pot preflop etc. - in this case, the best thing to try to figure out is what are you going to do if one overcard to your pair comes. If you get donked into or raised, is it ALWAYS top pair or better? Should you raise to protect your hand by trapping the majority of the villains for two bets even if you think the donker has you beat? If everyone checks around to you, does it mean nobody paired the overcard?)
The reason I'm suggesting you do all this work is because it's just not enough to ask the question, "Can I play 99 or TT like they're a preemie?". You have to understand WHY you should or shouldn't play it like a preemie.
I hope this post came across as helpful and not as me being a poker snob
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