A great breakdown and some good points of improvement that I agree with entirely. 

Your point regarding updating the exchanges to remove Shapeshift and add others is especially key, as it is always a big concern to many users as to how fluid the currency can be exchanged. If a currency is not seen as being able to be actively exchanged, it could be argued that many potential investors in the system would be turned off due to fear that their investment would be unable to produce a return that could be capitalized upon. Additionally, the more exchanges listed that take Steem, the widespread the system seems and thus the more appealing it becomes.

I also greatly agree with your point on changing the "What people are saying" part to a more useful set of people as I also had no idea who the people quoted were and thus just ignored the entire section entirely. This comes as a big shame because that section could be used in much better manner. If regular users' quotes are posted there in a more fluid and continuous stream, I think that some key benefits can come of it. Firstly, a vast amount of different quotes from people makes the system look greatly used and highly popular, thus appealing for people who are unsure about the system. Secondly, the ability for these posts to be verified on the blockchain and the knowledge that they are immutable can give confidence to more crypto knowledgeable investors that the posts weren't edited or redacted for optimal results. Lastly, given how people seem to be on Steemit, it should not be hard to find a large amount of posts that talk in favor of the system.

Thanks for reading the long post and some great ideas you have here.

TLDR; Agree with you, more marketplaces = better looking platform, revamping what people are saying is really important and makes the system look better + wouldn't be hard to find praise of Steem from Steemit.