May I ask what you are trying to accomplish? You really won't see any obvious change by using different developers, if all you do is develop normally or push or pull by one stop only. I'd just stick with D-76 and get more familiar with it. If you look over internet sites, including this one, you'll see very passionate claims on what each developers will do and how much better one is over the other or how different they are. My own experience with very commonly available developers such as D-76 and XTOL showed me changes are very subtle. Of course I haven't done anything exotic, except I recently processed my film with Dektol (which is really a print developer).

I hear a lot about Rodinal and Dianfine, so if you really insist, you might want to try that. But, until you get to a point where you can get consistent result from one developer, you really won't know the difference you are seeing is because of your process variance, your own eyes tricking you, or really the difference developer made. My suggestion is not to bother at this point.