That is the problem with split-grade printing - you lose direct control of the midtones, which is where an image's interest lies.
If you have a complete set of contrast filters then try making test strips of just the midtones with a #2.5 filter. Make a full print. If you want more midtone contrast repeat with a #3, if less then try a #2. After you get the midtones where you want them then burn and dodge to modify the shadows and highlights as needed.
A general bit of advice - VC papers have their best midtone response at grades #2.5 - #5. At lower contrast grades the midtones will lose contrast. The ideal negative for VC papers has full detail but is rather thin and low contrast. A good rule of thumb is to expose at 1/2-2/3 of box speed (rate a 400 speed film at 250-200) and develop for 15-20% less than the developer/film data sheet says. Film makers like to claim the highest speed they can; in the late 50's they doubled film speeds across the board and so the standard regime they recommend can be cynically thought of as a "1-stop push."
The "expose more, develop less" regime is the conclusion most photographers reach after they go through 2 weeks of "zone system" testing to find their "personal film speed" and "personal development time." Not that going through the testing is a bad idea: the benefit is the insight you get from the exercise rather than its outcome, a bit like an experiment in chemistry class where the outcome is already known but you do the experiment to learn.
If you want to continue with split grade printing you need to use two methods:
- If the negative is low contrast then you should determine the #5 exposure first using the black point, then give the overall #5 exposure and make a test strip with the #00 filter to find the white point exposure;
- If the negative is high contrast then you should determine the #00 exposure first using the white point, then give the overall #00 exposure and make a test strip with the #5 filter to find the black point exposure.
Advice from people who swear by one or the other do so because they commonly produce high contrast or low contrast negatives - and so both bits of advice are valid, just that you need to switch from the one to the other as needs must.
A rather technical paper on split grade printing is available at Darkroom Automation's web site
http://www.darkroomautomation.com/support/appnotesgmeasured.pdf. The paper is directed to user's of DA's enlarging meter but it gives a general discussion of the black-first Vs. white-first reasoning.
Another paper you might find interesting is
http://www.darkroomautomation.com/support/appnotevcworkings.pdf which explains why low contrast VC filtration results in a flat-spot in the mid-tone contrast.