Is it better for a hepatocellular liver tumor to be well-differentiated?

Yes. In general, well-differentiated cancers are more organized, more predictable, and less aggressive than poorly-differentiated cancers.
Yes. Hepatocellular carcinoma of the liver is a primary lesion usually associated with and induced by cirrhosis and the hep B or C virus. The lesion grows in the liver eventually showing up at several sites, spreading by the portal system. Being well differentialed slows the progress of the tumor allowing more time to consider resection, microwave ablation, chemoembolization or yt. microspheres.