I'm guessing (from the stand development) that you have shadow detail; your lack of contrast is due to insufficient agitation. In other words, you're using the developer in a compensating way, and compensating too much. It causes flat images.

Compensating (stand) development gives you more shadow detail without blowing highlights but it is an approach fundamentally in opposition to also obtaining sparkly midtones and highlights. Your highlights will be easily printable, but they will have lower contrast. They will not have "pop". Or if you do traditional agitation with Rodinal, you're likely to get good midtone+highlight contrast, but you will not get as much speed.

Picking one of each is a good thing, though it's a grainy combination it's a good one. I would suggest ditching stand development and doing normal development with about 5s of agitation every minute, Rodinal 1+50. You will get less film speed (200 or 320 probably) that way, but the images will definitely pop.