If I were trying to get cute about price I might try an Ichimoku Clouds chart alongside an RSI chart, mostly because it's what I'm most comfortable with in general.  They'll tell you perhaps more about the fiat side of the equation than Bitcoin though.  Bitcoin itself is tricky because prices are set at the margin, and once little enough Bitcoin is floating around because it's all been snatched up by hodlers, there's no telling how quickly it can jump up, seemingly out of nowhere.  These events seem to be incredibly hard to predict. If an S&P500 company tomorrow decides to start throwing a sizable chunk of BTC on their balance sheet it would likely dry up a lot of supply very quickly, as it's really just incredibly early still, for however much you may feel like you missed the glory days in the 2010's. At the end of the day, if you divide 21 million Bitcoin by 8 billion people on Earth and then multiply it by $76,000 (the fiat price of bitcoin at time of this writing) you get just about $200 -- let that sink in.

There are probably people who have watched these dynamics better than I have who could offer some insight into measuring how much bitcoin is "live" at any time and, in combination with some of the other dynamics, really give you a decent system to work with. But the chances of a black swan (or what's the word when it's an unexpected bullish phenomenon? a white swan?) event throwing your whole system out the window because everything's surging would likely always be pretty high, at least at this stage in the game. Recall that two months ago today we were around $54k.

At the end of the day what should likely shape your decision here are two factors: your outlook on global fiat liquidity dynamics in the relatively short term (<1 year - 3 years) as well as the overall outlook for Bitcoin to the extent you can really project this (with examples being outlook for regulatory changes, large government liquidations following seizures, or large institutions/governments adopting Bitcoin as a treasury asset or legal tender).

Personally I tend not to have the patience for all this. But it's an interesting thing to try to work out. You'll have to decide for yourself of course whether the risk of missing out on upside or the risk of buying a near term top is your bigger fear.