Currently, the Low Power Mode in Orion hibernates tabs after 5 minutes of inactivity. The issues are that 1) it's not necessarily uncommon to open a fairly large number of tabs within that 5 minute period, in which case the Low Power Mode does little to reduce RAM usage 2) users probably do still want the last 2 or 3 tabs to be kept active even if they were last used 10 minutes ago, since those are the tabs the user is most likely to want to be able to quickly switch back to.
I'd suggest that the low power mode be replaced with a couple of user-customizable tab hibernation settings. The user should be able to select a minimum number of the most recently used tabs to be kept active (e.g. 2 or 3), a maximum number (e.g. 10) before tabs are hibernated regardless of whether or not they were used in the last 5 minutes, and within the min...max range tab suspension would be decided by the five minute rule (or a user-specified time limit). Existing rules such as not suspending any tabs with modified form inputs or playing audio would of course take priority.
This could be made even better if the user had the option to choose a RAM limit in place of a maximum number of unhibernated tabs, similar to the RAM limiter in Opera GX, though I would not consider this an essential option.
P.S. The Low Power Mode pop-up refers to tab hibernation, whereas the right-click menu only offers tab suspension as an option. Is there a difference between tab hibernation and tab suspension in Orion (e.g. tab hibernation might correspond to completely unloading a tab, whereas tab suspension might be more like sleeping tabs in Chrome) or do they refer to the same feature?