I think that the Nova Series of phono stages are truly wonderful for their price point, like all Michael Yee designed audio products. The trick is to set them up properly for your cartridge.
Speaking of which, you will probably resent me saying this but IMO you will never wring the best performance out of either your DL-103 or Well Tempered tonearm when used together - this is simply not a good match. The DL-103 family is an extremely low-compliance cartridge that was designed for heavy, rigid, high mass tonearm. Simply weighting the headshell is not enough - that will not significantly change the tonearm resonance.
I speak from experience here, but YMMV. Good luck.
Speaking of which, you will probably resent me saying this but IMO you will never wring the best performance out of either your DL-103 or Well Tempered tonearm when used together - this is simply not a good match. The DL-103 family is an extremely low-compliance cartridge that was designed for heavy, rigid, high mass tonearm. Simply weighting the headshell is not enough - that will not significantly change the tonearm resonance.
I speak from experience here, but YMMV. Good luck.