Banishment has the potential to warp all future encounters around it. Temporarily halving the quantity of enemies your group faces will give you an enormous resource advantage that can easily trivialize encounters built around a handful of moderately threatening enemies.

If you need those hit points in addition to Prayer of Healing, then this spell is decent, but I have to wonder if casting another proactive 2nd level spell like Spiritual Weapon instead may have mitigated a bunch of the incoming damage while ending the damaging encounter faster. 

If you’re getting access to Sending, it's probably through Sending Stones, and that’s more as a convenience to mitigate metagaming than a particularly powerful magic item. Most tables just won’t want to spend a 3rd level spell slot on this, especially when the distance isn’t typically a major element you’re worried about in most games.

Daylight has an incredible look. You conjure a brilliant blast of light, a radiant explosion that rebukes all darkness. The problem is that’s kind of all Daylight does; it's a big, hour-long spotlight that acts as a super torch. And that’s rarely going to be worth a 3rd level spell slot. 

Magic Weapon is a terrible spell that exists for an unfun, poorly designed mechanic that has no place in modern gaming.

Mirror Image is an old classic I’ve relied on in multiple editions of D&D. It’s fun to watch your enemies get frustrated by wasting a great attack roll just to knock out one of your illusions.

The lengthy spell description covers all the bases pretty well. If you’re forced to participate in combat, Mirror Image is a good way to keep yourself alive a few extra rounds.

Misty Step gets you past traps, over moats, and into houses. It excels in combat, in exploration, and in role playing and infiltration moments. Hop onto the chandelier to bring it down, or onto the back of the red dragon mid flight! Get yourself onto the back of the horse fleeing with the kidnapper before they can get too far away! Put yourself in the ideal seat on the wagon without needing to call shotgun!

Dominate Beast is outclassed by summoning magic and hits a creature type games tend to pull away from in the tier you get it.

Ray of Enfeeblement isn’t something I’d recommend picking up and using regularly at 3rd or 4th level, but something to consider past 7th level when you’re starting to bank a lot of higher level spell slots and have some room to switch out lesser used lower level options.

Rope Trick isn’t going to be a wizard’s most cast spell, but as a cheap 2nd level tool, it's a blast to play with that will affect the game from the moment you get it until it ends. Clever players can juice this for all it’s worth, and even in its average use case, your DM is going to have to consider how they deal with it.

See Invisibility does less than it says rules as written, which is crazy to me. You spend a 2nd level spell slot to see invisible and ethereal creatures for an hour- to me, it's implied this removes the benefits of them being invisible or ethereal, but thanks to good old fashioned wonky rules interactions, it does no such thing!

Spider Climb is a 3rd level way to start engaging with the three dimensional fantasy world in ways you couldn’t prior. It fulfills part of the Spiderman fantasy where you’re sticking to ceilings and sneaking over arrow traps laid out on the floor. It gives you a tool for scaling shear surfaces in a new way, for a long time.

Suggestion is a spell with one of the most powerful potentials in the game for its level. Clever words paired with misleading circumstances can lead NPCs to perform in ways that radically shape the outcomes of the story. With a duration of eight hours, at minimum, Suggestion can act as a save or die to remove foes from a fight that they feel isn’t entirely necessary.

Web is an iconic classic spell. This is something straight out of 2nd edition, a spell to gunk up a dungeon corridor to light on fire with your torch. Its 5th edition translation leaves it feeling almost like it's out of place; the rules around it are complex, requiring a very specific environment to work at all, but in exchange, gives you a fairly powerful effect to play around with.

Enhance Ability is something you prepare for a single low tier encounter involving seducing a nobleman and then never again. It's an unremarkable spell with underwhelming text that doesn’t play well in a system that gives out advantage like candy on Halloween. You probably don’t ever want to spend spell slots on this.

Taking Dispel Magic at 5th level is a bit overkill, but finding room for it in the next few levels I’d recommend to most anyone. Dispel Magic is reliable, useful, and a way to engage with a kind of play otherwise challenging to interface with.

Positioning is critical in getting juice out of this spell, but when tactically cast, you know exactly what you’re getting, and can take comfort in this spell’s consistency. I think it shines brightest against a group of two to three bigger threats in tight corridors, but can also be a great crowd control tool to slim the numbers of smaller swarms of baddies.

Spirit Guardians offers you 3d8 damage a round each round you can maintain it to anything within 15 feet of you that you haven’t designated. If you can get 6d8-9d8 damage out of this, it will absolutely be comparable to Fireball damage for the slot, but needs to happen over time. 

Enthrall exists as an in game way to bring that vision to life. Here’s my issue; why can’t bards just do this without spending a spell slot?

Polymorph in its current form may be a bit too much, specifically for managing powerful enemies. This is the kind of spell that forced Lengedary Resistance to exist; a save or die that is so powerful and cheap that if something fails it, the encounter can be over before it begins.