The idea that per-rest abilities make the game less tactical is not true. Sure for some people, they will feel that they should never use their per-rest abilities because they might need it later. With this mindset these people will also never use consumables. The problem then is not with the combat system, but simply that the player’s mindset is not suited to this particular play style, otherwise you would also argue that consumables also make the game less tactical because the incentive is to avoid using them, thereby reducing the number of tactics they can use.
You've misunderstood my meaning previously. Although I used straight damage spells in my BG examples, I was trying to pick flashy high level spells and saying that they were more epic because their usage was limited.
That’s not how the spells in PoE are designed to work. The fact that most spells incorporate large areas which can friendly-fire forces you to plan in advance how to position them. Panic throwing spells when you're suddenly in trouble is not the kind of tactical combat I was talking about. What I had in mind was things like creating funnels for casting Fan of Flames, or pre-emptively laying persistent AoE spells into which you bait the enemy.
If you want to reduce the effectiveness of the spells and give them more uses instead, what you end up with is a massive amount of spells which you need to continually reuse over and over again like skill rotations in an MMO, where the player simply mashes the hotkeys on the keyboard in the same patterns. I find that kind of button-mashing combat to be tedious and boring.
On the other hand, when I scout out a difficult fight with a rogue, and I carefully combine a small number of spells from my wizard to penetrate the resistances of the enemy and disable or funnel them towards me, turning the fight into a complete stomp, then the fight becomes immensely more satisfying. Turning a difficult fight into a trivial one through careful use of spells is a rewarding experience, not something which detracts from the game experience.
Take the cipher for example; you can just mindlessly spam mind-blades every single fight, and then the combat eventually becomes repetitive and boring. That's why I prefer having the powerful per-rest abilities, because it means you need to change things up. What if you ran out of Slickens? You might have to place a web down and kite the enemies through it instead. What if you run out of fireballs? Maybe you have to lure the enemies into a narrow corridor and bounce Rolling Flame around. Maybe one fight, you can get away with just disrupting the enemy mage with a Thrust of Tattered Veils, and be rewarded with having more spells for a later fight.
Having limited per-rest spells makes combat so much more tactically intense than simply spamming mind blades until you run out of focus, then shooting a gun till your focus comes back. Imagine if the wizard spells were per encounter but weaker. Every fight, you would open with a few buffs like Eldritch Aim, then you would use the same CC spells every fight, first slicken then chill fog etc. It'll just become so repetitive.
Resource management is part of what gives meaningful choices in combat. If every spell or consumable I use is just going to be back for the next fight, then the proper way to play would be to use up all the spells each fight regardless of whether I really need to actually use the spells. It might appear more visually appealing when more special effects are occurring on your screen, but it cheapens the overall decision making in combat.