Ah hahaha,
I believe that's going to take quite a few DoD missions to get those 90hp augs, but, that's a pretty good choice, if you're willing to put in the time and effort to get (hell, I probably could use to do that and replace a few 50/55hp augs I still got left, OMG, effort . . .).
As for your charm, there's the that is unless your maxxed already on LDoNs. It's a single group encounter in the Freeport Arena. Mine's not maxed, I've completed around 30 or so of the 41 waves there, and those were pretty easy to do (had to stop when our MT needed to leave, it's actually easier when you have a chanter, we didn't). It has a few nice bonuses besides the stats, regen and avoidance, which are pretty handy to have (esp since most 1 group gear doesn't have very high amounts of avoidance on them).
I've not finished quest (Vestiges of the Empire), so I don't have much of an idea on how hard/long it really is, what parts I do have have been gotten while just messing around. A lesser, but much easier to get, range item would be . It is the cursor loot on completing the DS access mission Deserting the Ranks (which is where a part for the Vestiges of the Empire quest drops for the Blade, you could use this as an intermediate until that's done if you want). The other advantage is that the Plate doesn't require leveling up an item 3 times.
An augment that is worth working for is . It is a possible chest drop at the end of Arcstone spell mission #3.
If you check your , it shows no stats, there might be 2 listed in magelo, just find which one actually has the stats on it. Looking it up on Lucy though, it's not really worth it. +10% to crap dodge skill = crap dodge skill still. You would be better off putting an hp or DoN focus effect aug there IMHO.
Hope some of that helps, looks pretty good so far, now get to work !!! (and good luck

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