The Syncros have been life-changing for my teenage daughter (whose loss is moderate to severe), but they might be overkill for a mild loss and they are extremely expensive. You might be able to get by with an Oticon Delta, or one of the Phonak lower-level aids like a Pico Forte or a Claro. Make sure you find out what the HA trial period is in your state, if you don't like the ones you initially got, you can always take them back and try another model.
I think some of your choice will depend on whether your mother's loss is expected to get worse. If so, then it is better to get a HA with more range, provided that it still handles mild losses.
Personally, I don't like CIC aids -- when they have to go into the shop, you can't really get loaners because of the custom shell. But I couldn't care less about the cosmetic aspects of wearing HAs, and others are very sensitive to this. I personally think an open-fit Oticon Delta is just as invisible as an ITE or CIC of any brand.