- Like what you've got: Update. Really. The newer models are so much better than the original, and the original D1 had lots of modality and control issues that will frustrate you, all fixed by the D1h. On a budget, try a used D2h or a new D7500 or D500. But if you've got the dough, try a used D3, or a new D850 or D6.
- Dislike what you've got: Update. On a budget, try a used D2h, D700, D3, D3s, D7200, or even a new D7500 or D500. But if you've got the dough, try a new D850 or D6.
- Upgrade to mirrorless: Z8 or Z9, but you’ll be changing from DX to FX lenses.