Edge discussion

So, I'm still pretty new, but I'm not seeing the usefulness of a few edges.

The edges that I've either put to good use or could see as useful are:

Enhanced power
Accurate bolt
Powerful bolt
Shaped bolt
Melee training
Spell training
Toughness
Contingency

These are pretty straightforward and probably don't need discussion about how they can be useful, at least for certain character "builds." If anyone thinks one of these is not very useful, I'd like to hear why they think that and how some other edge or a certain playstyle obviates the need for it. For example, I think enhanced powere and toughness might not be worth it in the long run. They're a significant boost at the start, but if you can survive long enough, another edge might be a better investment.

I would like to hear what people think about each shaped bolt. I really like ball, but sometimes run into problems with splashing myself. Switching costs time, so the instances where I need to swap away from ball result in me getting smashed in the face if I do. Haste, quick charge, and wave might be pretty amusing, but costly at two edges.

Then there's the alchemies. Faster mixing times seem very underpowered in comparison to the above, but maybe it's more useful later on in games? Mixing things while you're getting rushed seems like a terrible idea at double speed and it costs two edges to get advanced alchemy. I think even if you could simply get advanced alchemy at a total cost of one edge, it probably isn't worth it. Does anyone have any ideas on how to use the alchemies in a way that's worth not taking a different edge?

And then charge conservation, held charge, and quick charge also seem underpowered. Conservation also seems lacking, to me. I don't really seem to get into situations where I end up losing my charge. Quick charge would probably be very useful for melee-oriented characters, at least, and might be worth it for bolt-oriented characters. But considering you need to get conservation first, I don't know if it's worth the cost. On the other hand, if it simply cost one edge total, it might be overpowered. Held charge seems better than conservation, but since conservation is a prerequisite, it doesn't seem worth the cost. Anyone have any input on how to use these well?

The school-related edges I haven't used enough to say much about. (I did say I was pretty new, heh.)

I usually pump Spell Training. I figure most of the other edges can be approximated later. Then I grab a contingency around floor six or seven, and Accurate Bolt and Shape Bolt (Ball) or (Cone).

Of the Scholarly Edges, I really like Fleshcrafter, as I'm an absorption junkie. Undead toggle sounds pretty good too; it can free a slot from my Undead Amulet.
I took both Light Edges once. It's nice to have the healing for free, but I already had full resistance for all elements, so I can't comment on the other.
The Astral Edges seem pretty nice, but I'm not inverted often enough for it to work. I usually get an amulet to toggle Inversion when needed.

I can't comment on the other two schools.

I think a Item Capacity Increase could be a useful edge. Maybe a +5 increase, and you can only take it once. It's not necessary at the beginning, but could be useful mid-to-late game when none of the other edges are too appealing.