- Like what you've got: Update. That 2.5mp is not enough, especially if you ever have to crop. Plus, despite the binning, that sensor just doesn't punch with the same weight recent DSLRs do.
- Dislike what you've got: Update. On a budget, try a used D700, D3, D3s, or even a new D500. But if you've got the dough, try a used D4/D4s, or a new D850 or D5. Of these, the D6 is the one most like what you’ve got that does the most, but note that the D1h was DX and the DX equivalent of the D6 is the D500. A D500 is a huge update from the D1h. Huge.