The longer you read UHH, the more expensive it gets.

If you can freely spend money on camera equipment, like what seems like the majority of the UHH community, then the Nikon Z50 with an adapter to your DSLR lenses will maintain your existing lenses.

But seriously: your D3300 is a fully professional-capable digital camera with the current industry-standard 24MP sensor. A Z50 is a $850 purchase, body only, that actually steps down in resolution to 21MP.

Is another $850 the cost of making you happy with your camera? Will it make you a better photographer? Only you can decide.

As someone who has done almost exactly what you are contemplating, I would probably move to the D5600. As others have stated this is a very capable body. If you just feel that you have to spend money then look at better, more capable lens and other accessory equipment like a good tripod.

I owned a Nikon D7000 which I really like, but got the itch to move up and traded it for a Sony A6400. The A6400 is a very capable camera. The Sony gave me 24 MP but other than that, I cannot say that it was that much better than the D7000. The menus on the Sony are more complex than the Nikon and Canons that I have used, but in my opinion are easy mastered with practice and some study. I certainly cannot say that going mirrorless was a great improvement in any aspect of my photography.

While the manufacturers pushed the mirrorless concept as an improvement in photography, I think that was more marketing hype than real progress. I see it more as an improvement in manufacturing technology for the manufacturers. By eliminating the mirror and all the mechanical workings they simplified the assembly, thus lowering their costs of manufacturing. Maybe these cost savings were passed on to the customers since, like computers and phones, much higher capability cameras are available at reasonable price points. There are advantages in mirrorless cameras for video which may or may not interest many photographers. The mirrorless cameras also depend more on software to implement new features or fix issues that arise.

I do like my Sony A6400. However, if I were starting over, and not being a fan boy of any particular brand, I would probably have went full frame in Nikon or Canon and built my kit around that body. There are solid reasons to go full frame. I can think of few to go mirrorless.

I am 77 and have not made the switch to mirrorless yet. Why? No reason for me to do it as my current Nikon bodies (D500 and D850) and lenses and accessories are more than adequate for my photo needs (lenses from 20mm to 500mm.)

If I were to switch, I would want lenses that work without an adapter. (Why introduce something between the camera and the lens?) For me that means new glass through 500mm. Nikon does not have the glass yet.Even if it did, that would mean I would have to spend $thousands to replace glass.

If I needed a small light weight camera for travel, or some other special purpose, then maybe a new mirrorless Nikon model with a new Z lens. Or a less expensive Nikon Coolpix?

If I were just starting out, then my thought process would be completely different.

I Presently own a Nikon D3300 & 5 Nikon Lens. I have learned and enjoyed my knowledge gained from my 1st DSLR Camera. Now, I am contemplating a New Camera, I think I will stay with the Crop-Sensor line, maybe move up to a used D5600 Body, since I already have 5 Nikon DSLR Lens. I have heard so much about the new MIRRORLESS Cameras, although I realize it would mean purchasing a whole new system of Photography Camera & Lens, not even sure I can afford my contemplated change. I am also at the age of 70 now and am not a Technology Genius, so maybe I have already answered my own question, "Should I take the Leap to MIRRORLESS, or be content with my current Equipment?? Ok, I guess I will leave this New impressive Technology to our Younger Generation.