There are a good number of people worried about 2 things relating to STEEM. First is Inflation, Second is that the Coin's Creators instamined 80% of the Coin. But these 2 ideas are both contrary. If the Owners instamined 80% of a whole, that means that there is a whole. And if there is a whole, then there is no inflation. Just because all the coins in the ecosystem haven't been created yet, doesn't mean that new coins being created = inflation. This is prescribed inflation. Just like with Bitcoin, when new coins are created this does not effect the value, because everyone knows that eventually the total number of Bitcoins will be mined. So the price is actually set with that in mind, and it promotes an air of scarcity, not inflation. So you can't say that 80% of something was instamined, and also say that the thing is inflationary. They are 2 contrary ideas.
And, inflation is not always a negative thing. Consider Devcoin as a case study, something like 180,000,000 are created every month, and distributed between less than 200 people (only 10% goes to miners, 90% goes to people who do other work), sometimes as few as 10-20 people . Just split up from 180,000,000 in to pieces (meaning each person gets tens of millions of coins each month). Devcoin has not inflated to $0, and retains its price pretty well.
http://coinmarketcap.com/currencies/devcoin/
Devtome is a Wikipedia type website where they pay you Devcoins to add to the Wiki, or to have Developed something/Added to the Project's Github. At one point they had a boom, where they had maybe 300 writers on their Wiki because they had people sharing it on Facebook and getting it attention. When they had 300 writers there were 300 people wondering how to spend their millions of coins every month (I personally made $6,000 in one month once), and people even started trading Gold for Devcoin. The price was going up and up and up, then they started banning people. And now it is back down to 20-50 people, and the price dropped. It's basically a small Oligarchical coin now. But it never lost its value completely.
STEEM on the other hand, already has users in the tens of thousands, each of whom will be looking for ways to spend their STEEM. And STEEM is already #3 on the charts, with only more and more people coming in. It is very very likely that STEEM users will eventually be in the Millions. Then there will be Millions of people looking for ways to spend their STEEM, and Entrepreneurial STEEM users, and Entrepreneurs who see the opprotunity in STEEM will open markets to those people. And as more markets open up, the price will only rise higher and higher. There are no where near 180,000,000 coins being made a month, so it will never reach inflation levels anything like Devcoin, and Devcoin retains its value. So inflation isn't really a thing with coins that have a stable community around them. Even if it's just 10 or 20 people. You could start a Cryptocurrency for your favorite sports team, or for a club you are in. The value of each coin is set by the value the community around the coin brings to the world. If you cash out with your STEEM you might be slightly hurting the value, but when you use that STEEM to turn around and add more value to the STEEM community, then someone is going to buy that STEEM right back up and might even raise the value of it.
Now for the 80% instamine problem. Is it a problem? If the founders of Steemit decided sell the 80% now that it is worth possibly hundreds of Millions of Dollars, and run off to the other side of the World, then it might be a problem. But I think that they want to see their coin work, and maybe even become the #1 Cryptocurrency in the world. Which would make them Billionaires. So if they aren't going to sell it all and use it for themselves, what are they going to do? I have heard that they said something about redistributing it somehow, maybe through tasks or lottery, there was no specification. But they could also use it to fund Steemit. STEEM is a currency, Steemit is their Organization, their Corporation. Steemit could, for example, buy Reddit. Or buy a Rideshare company and change them over to STEEM payments. Or buy an Oracle Partner Company to develop CRM, and UX, and UI on the level of Facebook and YouTube. They could create a Cloud, based on Blockchain, that we all have accounts for already. The 80% instamine can actually increase the value of STEEM overall, it can make it worth Hundreds of Dollars a coin. It could be the #1 Cryptocurrency.