Bitcoin Core checks for blocks THEN writes them to disk, and doesn't bother to verify they were written correctly, rather relying on its LevelDB database. On some occasions, that results in botched blocks. And yes, Bitcoin Core will fail to read these botched blocks if asked to.
Armory depends on the raw files for its blockchain data, this is when those botched blocks get in the way. You also can't access Bitcoin Core's DB since LevelDB is set to lock it at process level.
We could hack around that but that's too demanding, will impact stability, and reflects an underlying issues with your copy of the blockchain, which frankly you should fix. The long term solution which to be introduce after supernode and the new wallet format will be blocks over P2P.
See, this is your problem right here. You see it as a reason, but it's not - it is an excuse. The botched blocks are a problem, but you are not looking for solution, so you are not finding one. Core client works with these blocks just fine. I don't hear core devs saying "oh, we got a leveldb problem, here's a great idea - lets make you reload your whole blockchain"
Think of it in perspective: resyncing blockchain requires several days. Many of us have lives to live, and not babysit applications. Also, for some of us bitcoin is not an academic proof-of-concept, but a tool, meaning: sometimes you need to pay someone, not in several days when you get a chance to fix leveldb, but right now. Is it usable? How about that it also will result in 30-50gb of internet traffic? You have your funds stored in armory wallet, and this problem happens every couple months. Is that usable? Not on day-to-day basis. Many cable internet customers in US are limited to 200-400gb of traffic per month. So, for some of us, fixing this re-occurring problem requires spending a quarter of monthly internet limit. Is it usable? Maybe for those of us who were not thinking and put their funds in armory hoping this someday gets fixed. What is the value of armory after all these issues, why would anybody be even using it? You still need to deal with maintaining core, this doesn't change. But in addition to this pin in the ass, now you also must maintain it in a way that allows armory to swallow its data. Security? I would rather be using paper wallet, at least I can import it into another client when I need access to funds. Offline transactions? I concur, this is a unique feature, but is it worth going through all this hassle to just use this one feature? I strongly doubt so. Don't get me wrong - i tried using armory, I tried hard, and in the end it's just not worth it.
The bottom line here is: if your application is unusable, then it will not be used. You need to find a way to make it working without regular glitches, and preferably without requirements for major downloads, or it will wither.
Have you thought of maybe packaging offline transaction feature as a separate product? It does look like the only unique and useful feature that the other apps don't do better than armory