Compare what your points are worth across Amex, Chase, Citi, Capital One and Bilt, so you can see which balance to spend and which to leave alone.
A point sitting with a bank rather than an airline has optionality, and optionality is worth real money. You have not yet committed to a program, so a devaluation at any single airline costs you nothing, and you can send the balance wherever the award you want happens to be bookable. That is the entire argument for earning transferable currencies rather than loyalty to one carrier, and it is why the same nominal balance is worth more at Chase or Amex than at most airlines.
Chase reaches United, Hyatt and Southwest. Amex reaches Delta, Emirates, Singapore and Cathay. Capital One and Citi each have their own mix, with plenty of shared names like Flying Blue and Avianca LifeMiles. The practical result is that no single currency covers every route, which is why many people hold two. Before you assume a redemption is out of reach, check whether a different balance in your own wallet reaches it.
When a booking can be covered from more than one balance, the sensible order is to spend the least flexible points first. Airline miles that only work with one carrier, or a hotel currency you cannot move, should go before the bank points that could have gone anywhere. Keeping the flexible balance intact preserves your options for the trip you have not planned yet, which is usually worth more than the small difference in headline rate.
Programs change award pricing with little or no notice, and points are not a savings account. Balances tend to lose purchasing power over time rather than gain it, so a large hoard held for a trip you keep postponing is quietly depreciating. Earn toward something specific, watch the transfer bonuses for the moment your ratio improves, and book it.