The system should be crafted around a mix of security and easy of use.
No; security should be the #1 priority of the network. The "ease of use" side should be provided off the block chain. Those who favor easy over secure can have their cup of punch without there being a turd in the bowl.
If we can have trusted places where we can download software without the fear of them being infected with viruses/malware then we can have trusted operators/nodes so that some users can use only a lightweight client without burdening them with a full node requirement. You sound like this is something impossible, but it's far from being impossible. What's the use of every user running a full node if they can't trust the place where they download the Bitcoin Core software?
There are many different providers of hosted files and some are trusted (Firefox, Google, Bitcoin.org etc) and some are untrusted. A random invented example would be
www.OptimizeMyPC.com that promises to speed up your computer if you download their tool which is filled with malware/trojans.
We can have this with Bitcoin nodes too. This is just another business opportunity and this is very easily doable.
Again nothing constructive from your posts. Just the usual MP quotes and the usual and useless "limiting stuff is better". You have a very limited and pessimistic vision about this whole ecosystem.