It shouldn't be at "Random" intervals.
The Cursor should show up whenever you're accessing a Menu., now I'm not saying this is how I'd like it to work... as like you I'd prefer it to NEVER show up unless the Application Loses Focus or I'm using the Mouse to Select Menu Items.
This said I'd also prefer it, if it was themed... like a little Hook or Cutlass.
At least then it wouldn't be as distracting.
I'm not sure if this is "Intentional" Design (if so., yeah Rare... Please Re-Think it) or if it's a matter of simply oversight as they tend not to play on PC... in which case Rare, Please address this.
Still it's just default behaviour of the game you kind of have to get used to.
Most PC Players aren't going to complain about it, because well they use the Mouse and don't care / notice.
There's actually quite a few User Experience decisions they've made for the PC that I wish they'd actually spend some more time addressing.
Control Schemes is one of them... Acceleration on the Xbox 360 / One Controller is FAR too Severe, and that Mice don't have Adaptive Acceleration and Sensitivity based upon Pre-Determined DPI (Per Resolution)., is well less than ideal … but heck most Games don't do this, so not going to really fault Rare for this; just something I think would be good for Moral of all Platforms and Control Methods.
Another is the reliance on the Xbox App and Windows Default Live UX instead of mapping this to in-game Systems. As well as Rare pushing for said common Xbox "Guide" Functionality to be added as part of the Game Bar... maybe they are, but simply not having any solution for needing to switch between Apps while playing at Launch is simply Bad.
A Small Independent Studio like mine asking for such... sure is going to get ignored by Microsoft; and most Big Studios don't care because they'll just dump their Game on Steam where most people don't even use said Features; and it does kind have such.
(Still Origin and even uPlay … heck about the only thing I can praise uPlay for lol., simply have far better In-Game Overlay for their App Controls)
I'd like to see Patch Notes on the "Message of the Day" (which is STILL just a Thank You Message) and I'd like to see an option to Enable / Disable the Intro; as hammering the "Skip" button each time I start the game so it doesn't take 10min just to start is annoying and just adds a layer of additional Boot Time Fluff that's unnecessary.