I actually like most of the indie mages. True that none of them can hold a candle to dedicated national mages with similar paths, but for e.g. nations that don't get nature picks, most indies are absolutely invaluable to get it started, since even a N1 mage can find a lot of important nature sites (such as the various Enchantress sites).
Of the Amazons:
- Garnets provide cheap blood hunters and can provide a blood magic jumpstart to nations without blood. Gryphon Riders are expensive and of limited use, but fire immune infantry is always useful. Especially if you fight someone who likes barbecuing your troops.
- Jade Amazons have the most powerful mages and can provide W2, N2 and D1, depending on random picks and absolutely kick-*** sacred cavalry with the right bless.
- The Onyx Amazons have H2 priests that have a 50% D1 and 10% E1 on top of that AND mountain movement, plus their sacreds aren't too shabby, they just tire quickly. The sorceress is a guaranteed Death searcher for non-death nations and rare ones can get D2, which can open forging options. Decently armored, speedy mountaineer infantry, which can be good in EA games.
- Crystal Amazons are the worst. They provide guaranteed astral and A1, which can help find some air sites (Silver Order if you're lucky) and increase air income, but that's about it. Lizards are more common and also give astral, so the only use is for air really. And speedy archers, which most indies aren't, but not comparable to woodsmen for movement options.
Druids, Lizards and the various Tribal shamans all have N1 and possible other picks that (if they manifest) may or may not be useful depending on national magics.
I expect poptype indies to be more useful in longer games and large maps, depending on site frequencies and difficulty of research.