How to get the best outcome out of comp. planning conversations?

It's a good conversation to have, but to be honest, I'm not sure the impact it will have. At most of the big tech cos I know about, the manager may have some input on how much bonus/salary/equity to give you, but they can't control the distribution. So perhaps my first question would be to inquire how compensation decisions get made.

At the very least, it's worth bringing up comp to your manager. This communicates that you do care -- this alone probably gives you more compensation compared to someone who appears happy with everything.

The other suggestion I have is to talk to your peers -- they'll have the most actionable insights about comp, especially if they're in the same org. For example, as a matter of policy, Meta doesn't change your comp if you get an offer at another company. However, Google certainly does. So one option could be to get an offer from a peer company (Meta, Snap, etc) and present that to your manager.

Are you unhappy with your comp now? If so, why? Are peers on your team with similar impact paid more? Are new hires getting larger offers (they always will)? Are outside companies paying more?

It’s OK to mention you are interested in expanding your impact, and for your compensation to match the impact you’re having now, but it probably won’t move the needle that much. Controlling the inputs (your impact, over delivery against role and level guidelines) has a real impact on the comp output. Your manager now doesn’t really. High ratings and promotion can be impacted by some politicking, but those are what get you paid, not talking now.

Outside offers can have an impact but it’s a weird game to play that I don’t love.

My view is that at big tech, your comp highly correlates to your perf rating. It's even worth while to bring up that you do care about perf rating through out the years and during the weeks when perf ratings are being decided. After the perf is decided, there's limited things a manager can do. Some companies might be able to change RSU / cash composition given the TC stays the same. At my company, my manager could request a 1% base adjustment, but I heard those requests are rejected a lot this year.

I agree with Rahul that it's worthwhile to communicate with your manager that you do care about perf ratings / comps. Performance is always subjective - especially when deciding on a boundary situation. The manager might want to try a little harder to bump up in your case as compared to someone who did not express interest. Also note that expressing interest wouldn't bring someone from the last quantile to the first quantile.