If you feel that the most effective fundamental channels vary from strategy to strategy, then how would you differentiate between channel options to choose the best tactics for a particular play?

Test, test, test. Have those fundamental channels built out so that you feel confident you can hit your ARR/pipeline goals with them alone and always save a bucket or time/money to experiment. That is the only way you'll learn what work for your business, stay relevant and push the business forward. when something shows to be promising, pour gasoline on it. When it doesn't, kill it fast.

This testing to prove out what does/doesn't work also requires you to understand the data of your organization so become an expert in your attribution model, lead scoring, lead/op statuses, lead routing etc. - all revenue operations - so that when you have the data, you understand how it all landed there and you can pivot faster.

Always base it on revenue performance. When evaluating any channel think about the customer acquisition cost in that channel compared to the total lifetime value of any customers required from that channel. If those economics are not positive, you shouldn't be in that channel. There is too much pressure these days to be in every single channel. It's not necessary. What I've found is 20% of the channels you're in drive 80% of the revenue results. So keep testing until you find that 20%

I recommend viewing this question from the perspective of a demand generation toolbox. From strategy to strategy and based on the goal at hand, you will use a variety of tools. This is the nature of demand generation.

If you factor in seasonality, product offerings, and just pure human nature, the channels and tactics will need to be tested. This does not mean that some tactics and channels aren't consistent. You will have trusted channels that are more mature and better measured. This essentially comes down to the goal for a particular strategy.