You should look into contextual realism. You might find it interesting. It is a philosophical school from the philosopher Jocelyn Benoist that basically argues that the best way to solve most of the major philosophical problems and paradoxes (i.e. mind-body problem) is to presume the natural world is context variant all the way down, i.e. there simply is no reality independent of specifying some sort of context under which it is described (kind of like a reference frame).

The physicist Francois-Igor Pris points out that if you apply this thinking to quantum mechanics, then the confusion around interpreting it entirely disappears, because the wave function clearly just becomes a way of accounting for the context under which an observer is observing a system, and that value definiteness is just a context variant property, i.e. two people occupying two different contexts will not always describe the system as having the same definite values, but may describe some as indefinite which the other person describes as definite.

"Observation" is just an interaction, and by interacting with a system you are by definition changing your context, and thus you have to change your accounting for your context (i.e. the wave function) in order to make future predictions. Updating the wave function then just becomes like taring a scale, that is to say, it is like re-centering or "zeroing" your coordinate system, and isn't "collapsing" anything physical. There is no observer-dependence in the sense that observers are somehow fundamental to nature, only that systems depend upon context and so naturally as an observer describing a system you have to take this into account.

Quantum mechanics and relativity are, at least currently, incompatible theories. Relativity depends on continuous things, which is why it has singularities and what not. But quantum mechanics has minimum discrete units that don't play nice with gravity and relativity.

Also, it's still an open debate as to whether quantum mechanics is applicable to all sizes of things. There's some consequences around that being the case and it's one of the suggestions for an assumption resolving recent paradoxes around incompatibilities between the theory and our expectations for behaviors. If it does apply to larger objects, the consequences are basically that either there's no free will and superderminism is true or else that quanta don't actually exist until observed.

In fact, currently we haven't been able to observe quantum behavior in anything large enough to measure gravitational effects from. Which may be where a fundamental limit exists, given the incompatibility between relativity and QM.