I think you are approching this development effort slightly backwards. You are trying to solve the abstract development "problems" before creating your program, instead of creating your progam ... and trying to improve on problems you actual run into while doing so. That's not how good design, architecture, patterns and experience is built. There are general "goals" and "strategies" in programming (goals include: don't repeat yourself, keep it simple stupid, clean readable code, consistency) (strategies include: single responsibility principle, liskov substitution principle, tiered design, factories, polymorphism, interfaces, etc).
Understand that the main goal is that for any given program there are a certain set of lines of code that MUST be written and executed by the machine to make the program work (such as the reading of files, bliting to screen, computing of damage, starting and stopping of sound, processing of input etc). But these usually make up only a fraction of the actual code in a program. The rest of the code is organizational overhead. While there may only be a few ways to draw a texture on a triangle in a video card, there are HUNDREDS of ways to organize and layer code that eventually does so.
These organizational structures, patterns, abstractions ... they have NO INTRINSIC VALUE. They have value only to the extent that the humans who use them find them helpful for getting to the desired goal. Accept that your program will not be able to be 100% perfect. Accept that there will be "some" repitition of code, some ugliness of design, and some inconsistency and difficulty in maintenace. When trying to get a progam working, the first question should not be how to make it fit a principle or ideal. It should be how to make it work, to do what the computer needs to do. And then, the second (or third or fifth) question should be "Is this code as clean, well designed, performant and or pleasing to me as it should be?".
You don't learn to make high quality guitars by asking the luthier to explain to you the "right" ways of making them. First you learn how to do a specific detail - staining or polishing wood perhaps, or attaching fretboards. Then once you have done that thing, you ask as to how you might improve at that thing. Then you move on to another. And after years, you hopefully are good at all of the skills required to make quality quitars (or computer games).
So what I am sugesting (in a long winded and not so obovious way) - is that you bring an ACTUAL EXACT and REAL example of something you are actually doing, and ask for how to make THAT THING better.
For instance, if you have a "Sword" or "Weapon" interface or class, and perhaps have made it data driven, and perhaps are now looking at your code, unhappy because you feel like it is too much duplication, you then would be asking, "How might I generate this set of artifacts (or their equivelent) from a single source to reduce this duplication?". By posting your existing code, and your question that way, people can help you factor out commonality in your design, or push you toward a more appropriate abstraction that would not create as much redundancy.
People cannot tell you how to generate code in general, or recommend or judge abstractions in general ... but only in specifics.
I will give you my example. I started on some simple 2D game stuff about 15 years ago. Early on I produced some results but had really ugly code and bad abstractions. How do I know they were bad ... only because I had a hard time keeping strait what code was responsible for what feature and where to change things as I made my game better, without creating bugs. So over time, my code moved toward certain shapes. And many of these shapes eventually settled and haven't moved much in many years ... because they are now good expressions for what I need them to do (in a relative sense). I can't remember my "bad" designs from 15 years ago. But my current concepts are fairly simple. These are NOT necessarily designs OTHERS should use, they just work for MY code basae. I have "game resources" which represents things which need to be managed by resources managers (such as images and sounds), this general concept is not a class but a term, I have actual classes for the different resource domains including "ScreenResource", managed by a ScreenManager, and SoundResource by a SoundManager, etc. There is some repitiion here, which I have factored into ResourceUtils, but mostly they are different. I have GameObject which represents everything which interacts with the "game world" and affects the management of "game state". I have a Game base class which represents an instance of the logical game, which is subclassed for each logical game such as ColorInvasionGame, which is different than my Application class which represents a client progam that the user uses to play or serve a game, which has derived classes such as ColorInvasionWin32App and PokerServerApp, etc. When it comes to my simple 2D game sutff, I have IPhysicalObject which is anything with a position in the "physical" game world, and IMovableObject which is a physcial object that may change position, and IActorObject which is a movable object which may cause changes, usually via user input, AI action, or timers or other event triggers. Of instance an asteroid is a movable object, but a pirate ship is an actor object. Each of these adds an API to interact with the additional features it provides, while letting the common simple physics/collision engine work on physical objects.
The above has nothing to do with your original question, because I still need more details about the code you "have" that isn't as good as you'd like to have, to give you better advice. The above is like 10% of the primary classes of my game design, which is broken into over 100 classes, about 30% of which are heaviliy data driven (and would be approprite as DB tables or configuration files) ... there is no 1 size fits all design. My engine doesn't support 3D, doesn't do real physics, can do either turn based or real-time, and is only made to handle the small indie hobbiest stuff I like to play with in my spare time. It is underwhelming and poorly designed in some areas, and overengineered in others ...
Just make code work, do something you like, and make it better piece by piece.