Incorporating a time dimension to domains, such that it's explicitly recognised, and greatly restricting transfers, would be one element.
Ownership of domains should sit with the registrant, not the registrar.
Characterspace should be explicitly restricted to 7-byte ASCII to avoid homoglyph attacks. It's not a shrine to cultural affirmation, it's a globally-utilised indexing system, and as such is inherently a pidgen.
Other obvious pain points:
- BGP / routing
- Identity, authentication, integrity, and trust. This includes anonymity and repudiation. Either pole of singular authentication or total anonymity seems quite problematic.
- Security. It shouldn't have been permitted to be baked on.
- Protocol extensibility. Standards are good, but they can be stifling, and a tool for control. Much of the worst of the current Internet reflects both these problems.
- Lack of true public advocacy. It's deeply ironic that the most extensive and universal communications platform ever devised is controlled by a small handful of interests, none answerable to the public.
- More address space. IPv6 is a problematic answer.
- Better support for small-player participation. Servers are still highly dependent on persistence and major infrastructure. A much more robust peered / mesh / distributed protocol set that could be utilised without deep expertise ... well, it might not make things better, but we'd have a different problem-set than we face presently.
- Explicit public funding model for content, and a ban or very heavy tax on most advertising.
- A much keener, skeptical, and pessimistic early analysis of the interactions of media and society.