This part always gives me pause.
@koraks seemsm to frequently state that scanning will never (my words) give unbiased results. For B&W and transparency films it seems that examining the negative/positive is quite instructive, but less so for color negative. The company I use for color negative provides a "proof sheet" but its not clear to me if the scanning for that has been corrected in any way, as a whole or on individual frames. For general impressions, though it seems good enough and may fulfill the level of quality for this great suggestion.
There are many who only scan, and sending off for prints may be too expensive . In the end I guess it up to the user to decide scan or pay for printing.
In terms of color negs, ordering up a basic scan along with digitally printed proof sheet from the lab can have serious shortcomings unless you opt for an expensive scan. And the smaller the sampling area, the more error you are likely to get, with 35mm originals being the worst due to their small size. Whenever I have gone that route testing an unfamiliar new color neg film, I submitted 120 size exposures instead. There are real limitations to automated scanning and printing lines, especially on a tight budget.
As OP question concerning zone system, his ID states that he is a 35mm shooter I did not address color.
In terms of contact printing, a contact made on VC paper with #2 filter, why would an enlargement have different tones? After 57 years of making contact prints with contact paper, standard paper VC, FB, RC, I have not seen jump in tones. It does take a loop and light table to really get a look. Contact paper tends to be more problematic as it does match printing paper very well, not sure who even makes contact paper. Then again for the test roll if OP prints he can made a set of 5X7 proof prints.