I'll just get to the point: I didn't find anything bad about it.
I know that many people were looking for an expansion or even a new game entirely but considering what we are going to get, it's not that bad.
Let me explain from my point of view:
people are complaining about lack of content - well, it's a grinding game. most grinding games reach a peak at some point and story wise, yes, you have enough lore to make two more expansion if they so choose to but for now, the story is finished, so not having new story to uncover is not that much a thorn in the side as people make it out to be. Also, being a grinding game, it all boils down to "Kill->Loot->lvlup->Repeat" so,eventually, you'll end up doing exactly that and whatever new content they'll put out, you'll end up doing this exactly this so, the "Lack" of new "Content" is not such an issue with me as it is with other people in the community. besides, comparing D3 to other games like Hearthstone that gets a new expansion every half a year or so, or to HotS where it's still the same content (essentially) but done in a different way (new heroes, different maps, etc.) is kind of moot.
Micro-transactions - I don't think that it would be that much of a thing in other regions other than the Chinese region and the sole reason for that is that while in other games such as CS and other FPS games, there's isn't really much value in Micro-transactions in D3. i don't see people paying 10 Euros for cosmetic wings and such.
I think that with all the patch content we've gotten so far - the Kanai's Cube, more sets, a new region - it would have been easy for Blizzard to say "Well, we can push it all in an expansion and let them deal with what's there is for about a year or two" but they didn't. considering all the content we've been given over the past two years, pushing out Character Packs isn't such a bad thing. it's a form of revenue generating that many gaming companies do
TL:DR - i wasn't excited but i wasn't disappointed either. All in all, i find the new Class very appealing, the QoL changes much needed and that's all i need. when the time comes, new content will emerge and people will rememeber why they played this game for hours on end.
I have mixed emotions on this years Blizzcon. Yes, I'm most definitely excited about the Necro class coming but completely crushed that it isn't coming by way of expansion. Let me explain why. Coming as a simple character pack will only give me about 1-3 months of semi new content. After that first season with the Necro then its right back to the same old thing. If, however, they went with an xpac to release the Necro we would most likely have received a new act and a bump to 80 level cap. For me that's up 7 seasons of new content, by rotating out classes each season, trying out w/e new skill they could have added for each class and grinding out all the higher level gear for each. If you look at it like this, which is really more appealing to you for your money?
Don't get me wrong. I will most likely be getting the Necro Pack as long as the price point seems reasonable for what it really is we will be getting.
Micro-transactions: I completely disagree with you on this point though. While, yes, $10 for wings and such is high end, I think plenty of people out there would gladly piss away $5 for such items. There are farming communities in game for all these transmogs and wings now. It wouldn't hurt for them to atleast stick their foot in the water and see what it's like.
i see what you're getting at with the Micro-Transactions. As far as a new expansion and bumping up the level cap, while part of me want it to feel progress, i'm worried that it would have the same effect on players in the game as MoP and WoD had on players - a new zone, a new class but progression was minimal and not really impactful and you ended up doing the same thing. I know it's kind of contradictory to the fact that you get a Character pack with no new changes but it's a matter of opinion. Eventually, i'd like a new story to play through, a fresh experience with the end game (which we sort of gonna get with Challenger rifts) and I hope that we'll get to have that but for now, with what they announced, i'm content to a certain extent.