Playing devil's advocate here (I don't think software patents should exist, or at a minimum the bar should be significantly raised in what constitutes a patentable idea):

What if I'm really just an inventor type, and I don't have any of the skills or the desire necessary to go about making money off my patent. I imagine negotiating with Google, Microsoft, Apple, etc. isn't a simple make a phone call and start receiving checks type process. Not allowing an inventor to sell his patent limits seriously limits a major avenue of revenue for the inventor.

Assignment of IP to the employer is presumably a clause in just about every employment contract any founder ever imposes on new recruits to their startup - on pain of them leaving and trying to hold the startup hostage over their contributions. What you're suggesting, I fear, is just too blunt. What about a bad faith doctrine, forbidding NPEs (non practising entities, aka trolls) from enforcing a patent - only those who exploit their IP in-house can enforce their monopoly against others? Or, alternatively, linking one supposed purpose of patent protection - disclosure of ideas to the world (I gather that incentivisation to innovate is another) - to the ability to sue. So for example, only patents that are cited as prior art in future applications can be enforced against third parties. Evidently, making the 'obviousness' and inventive step blocks to patent granting more potent should be the first step considered. Who loses, exactly, by making patents harder to get? Can't IP advocates accept that this would make creators strive to be more creative or innovative?

So you ban sales, and instead this company sells itself as a "patent enforcer", makes deals with inventors, and takes a percentage of moneys gained. They can even pay an advance. Practically speaking, this ends up the same as when you can sell them.

The ability to sell patents give investors some downside protection when funding a startup. Every VC I've ever pitched to asks - "What's patentable". If you don't end up making money off selling a product / service, at least there is the hope of selling a "asset"

> If the patents were created to protect inventors

They weren't, they were created to get inventors to disclose their inventions to the public so inventors wouldn't take their trade secrets to the grave with them.

Giving inventors a limited monopoly was the means to that end; why else would they disclose their secrets?

It'd be nice if the person you sold it to at least had to use the patent before they could start suing people.