My favourite class in PF1 was Life Oracle. When I first read the PF2 version, I hated it. The more I read and look at all the options, the more I like it.
Spells: Angelic Sorcerers have more spell slots. Clerics have divine font. Oracles have better focus pools. They start with 2 points and 2 focus spells (revelation and one domain). Where the sorcerer and cleric have to spend feats to refocus 2 or 3 points, oracles get those for free 1 level earlier. All of the life revelation focus spells are centered on healing. Life-giving form is just awesome.
The curses:
Reduced healing is rough. However there are ways to help mitigate this. Healer's Blessing gives you a bonus to healing that would basically cancel out the curse (though you're technically activating your curse to negate the curse). The feat Godless Healing increases the amount you receive from Battle Medicine, which helps mitigate some of the reduction. These are just a couple of examples.
Being the only one able to heal yourself with magic will vary in impact depending on your group's play-style. In PF1, whenever I played a healer, I was usually the only one casting healing spells. In PF2, battle medicine is probably the most common method of backup healing anyway. So the effects of this curse seem worse on paper than they do in practice.
Keep in mind that you still get the full effects from spells/abilities that grant temporary hit points. For example, if you have an arcane or occult caster with the spell Endure (from Gods and Magic), they can use that as an alternate means of keeping you up if needed.
The benefits:
d12 to healing is a nice little boost. It's weird that it only applies when all targets are living creatures. The cleric feat Healing Hands makes it a d10 with no restrictions. Life oracles are basically hemorrhaging positive energy; they should be deadly against undead. This is probably my biggest beef with the class.
The extra little healing when casting a non-cantrip spell is not major, but it is still not bad either. It also has the positive trait, so if you're fighting undead, you can use it as a damage boost instead.
The major curse can be either really good or really bad. If you're fighting living creatures, you risk healing them and if you're low on hit points you risk dropping. That's why you only reach this level of curse when you absolutely need to. If you're fighting undead, this is a good boost to damage - cast a high level heal spell and it follows up with a secondary smaller heal spell for extra damage.
People often forget that healers make great slayers of undead. That was my favourite aspect of life oracles in PF1 and it's still strong here, especially with life-giving form.
If you only look at the spells per day and curse effects, it seems like a bad class. But once you start to explore all the other options there are and ways of mitigating the bad (I only gave a small fraction of the examples out there), the life oracle is actually a decent class.