The problem I'm seeing, with all these topics, is that a large number of people come in and bury the topic in "How else you gonna do it lololololol" posts, without actually bothering to read the solutions provided. Those that do usually only attack a single solution, usually the most flawed, and make a declaration based on that. This is extremely frustrating.
On the other side, you have a lot of people arguing that the reticule needs to display near-pixel perfect accuracy; that what is displayed on the screen must be an end-all be-all for exactly where the shot goes. This needn't be the case, either, and the failure to understand this is also frustrating.
The choices aren't between "completely random selection" and "pinpoint accuracy". You can, indeed, make a system that displays a "cone of fire" without just being random, or pseudo-random. In my opinion, the best solution is to have a "Flawed hud", where it may display a cone of fire, or not shoot directly at the reticule, but where the shot actually goes, in spite of all this, can be determined by a player who pays close attention to factors not directly displayed on the hud. This can include the position of the weapon on the mech, the angle of the mech, current movements, windspeed, shot recoil, terrain, etc. It should be possible to predict where the shot will go, with some accuracy. It should just be amongst the hardest things you will ever do in a videogame.
This is better than random because it allows a much larger development of skills by the person behind the keyboard, and makes sure games are not decided by rolls of the dice. This is better than pinpoint accuracy, because it's hard enough that only a rare pilot will be able to make use of it, much less regularly, and doesn't clutter the screen with "extra reticules". It means that the average player will more or less have a "random cone of fire", but there will be experts who can get around it.
This is called Having your cake, and eating it, too.
And before you start railing on about some other unrelated point, please
read this, and think about it before posting your dissent.