HCG is used to prevent testicular atrophy if used during a cycle, it also has another benefit of making PCT easier if used as such. It can also be used purely for PCT to help with longer/more suppressive cycles. If used for PCT, the fact that it in itself is slightly suppressive must be taken into account when planning the duration of your PCT. IMHO unless you have been on a long/suppressive PH cycle, there is no need for HCG with PHs.
12+ week test cycles, good idea to have it.
Fina, Deca, and other "massive shutdowns" a good idea as well, although shorter cycles (not with deca, but Nand PP), you can get away without it if the doses are low enough.
ManBeast