Pyroclown,

We got a lot of good things going on here but also a lot of things that don’t go well together.

First,

When a billionaire futurist is killed —

This is the inciting incident you included which doesn’t seem to link to the next part of the Logline: the MC. If the billionaire is important to the MC, then state that, otherwise, you can cut that out and just begin with the MC and her story.

Vengeful ex-assassin —

Sounds weird. A good assassin should be disciplined and almost free from emotion to be capable of doing their job.

Forced to confront her sanity —

May sound intriguing, but it’s vague and really not a special thing. Everyone has to maintain sanity on some level.

Discover who is manipulating memories… —

Here we have what I hope is the meat of your movie, the part I want to see played out. The sci-fi element mixed with the contemporary killer for money.

If she’s already a ‘retired’ assassin, then why would it matter if she retains ‘the world’s most feared killer’ title?

The assassin’s life is not a subject rarely explored, so you need to come in with a very fresh take on this genre. Hope this helps.