I would not recommend a slow film like PanF+ since it will show every skin blemish. This film tends to build contrast very quickly and should not be overdeveloped.
As for degradation of the latent image you are speaking of months. Still if it is a concern then shoot 24-exposure rolls or bulk load a small number of exposures.
As far as grain, Pan-X and FP4+ are comparable. Your comment about HP5+ has been expressed by others on APUG. As far as using Rodinal this developer will produce coaser grain than Xtol.