groundbreaking and thought provoking! 
u mistyped primtive btw.
Ethereum stuck to primitives or assembly.. And a double directed graph would cut down dev costs and ease of use on primitives.. however the million dollar question is: Is there a case you can think of where you would not want to use a graph but use primitives to solve a problem?
I guess vitalik assumes others will build on top if there is a market todo so while we give a leg up on beginners to solve problems quicker but if its a subset of problems then there is a case for primitives or assembly still. That is when will flexibility of primitives be needed in this context where a graph wouldnt work for a layman?
It's also possible that Vitalik simply over looked this. Building something like Ethereum is hard but I think if you're going to build a scripting language you need to make it high level. Right now they have scripting but as a person who can read several programming languages their scripting is awkward and low level.
I think now that they have the resources the Ethereum team should make a scripting language as much like Python or Javascript as possible. You want something which has minimal syntax for people to learn and which is powerful enough to do the job. Python is good as a scripting language because it's powerful but the syntax is very simple.
Serpent is supposed to be like Python and it's getting closer but it's not quite there. I think the competition between Bitshares and Ethereum should be on making it easy to develop for. Whichever DAC is easier to develop for will certainly win over my attention and I would think most people who aren't rock star developers at the same way.
C++ is not the language people will want to mess with when dealing with people's money. Javascript on the other hand is easy and so is Python. If it is easy people will feel confident enough to write code and if projects can be completed in weeks instead of months people will be more likely to make time to do it.
They have serpent and solidity working and full IDEs in development. We will not beat them as a smart contract platform unless we outgrow them first. More likely we will just pull in their VM once both of our systems are more mature.
We are basically all-in on BitAsset adoption and very basic financial services.
If we are all-in on bitassets then shouldn't our priority be to get the protocol stable so we can launch 1.0 and have no further hard forks a for a long time? Only then will we be able to get gateways, our biggest priority.
We already have the killer app, but it's super difficult to get hold of because gateways don't want to integrate with us because our system is still unstable. I think we should have just focused on getting the last UIA changes implemented, and then only focus on UX for the next 6 months for the amazing products we already have. We don't need scripting in the short term, there's not any evidence in the market that it's actually profitable or useful, only hype.
I dont think we should be beginning on working on even more complicated stuff now if it doesn't actually give us any marketing advantage over ethereum. It makes no sense from a business perspective. We need to get our product ready, and then launch it.