Let's go through them one by one:
1) Secret inheritance of lost arts - are they even good? Because if they are lost, they might not be that hot. You may be incompatible with it too or not have the materials to practice it, like how women couldn't practice the Sunflower manual because they don't have the materials for it. My sect should already have arts of their own and they are good enough.
2) Ability copy.
@ArrogantYoungMaster explained it.
3) Regression is only good when you have critical knowledge that you are certain will not be swept away by domino or butterfly effects. Otherwise, nah.
4) Heavenly-grade spirit root - out them all it is the one who I consider the most optimal because it is already a resource onto itself. Simple and to the point.
5) Memories of past lives - yeah I'll do without memories of being a hungry ghost, an animal and a sufferer in hell for strange eons for now thank you very much. Whoever chooses it is more likely to go insane or obtain enlightenment than help a sect.
6) Analyze skill? It is second best out of them all, but I believe that it can cause a reliance and make the user lazy when thinking. Ossification of management is a curse.
7) Dragon spirit beast companion is not an acual dragon because dragons are not spirit beasts but divine beings. Thus it's probably something like a drake or a wyvern and feeding it will make you go broke, they are tempreramental and 8) will be able to buy one anyway.
8) Being rich can be good if you're old money. Being a noveau riche is good, but very troublesome. I don't want problems with taxes.