So a couple things to note: I tend to use Heroes in chariots (so cover becomes more important), and skycutters are (at least on warhall) my chariot of choice, followed by Tiranocs. I think the "Chariot Runner" abilities are actually better for shooting chariots and cover against shooting (while still setting up for flank charges) than covering against charges - especially as at T4 they are very vulnerable to shooting.
I've knocked up a few scenarios below on Warhall to demonstrate (note: not from a real game but absolutely the kind of thing I've done in real games).
Scenario 1: Shooting Cover
I've set this up with a flank charge in the making as well but this isn't necessarily going to be the case. The basic principle here is that the Shadowwarriors are being used to cover against some handgunners and a hellblaster volleygun (24" range) - which is one of the deadliest ranged weapons for us and matches the range of the Eagleclaw BT. SW move in then the chariot moves and pivots for the supporting charge - you're now setup for the support charge and get a round of shooting against the shooting targets with the 360o firing platform. Even if you fail to kill the hellblaster, your chariot is still unlikely to get shot up. Skirmishers -1 to hit and long range will soak most of the shots.
Scenario 2: Chasing Down Artillery
Setting up a turn 2 charge on artillery/shooting placements using Scouts and Flying. A is the "not within 12" of the enemy" scout deployment rule. SW can move 10 or 5 (B) depending on what you want, but even if they move only 5 to allow shooting you can still reach within 10" of stationary targets (no stand & shoot at that distance (D) ) and perhaps even if they move. 12" is your minimum charge range so successful charges are practically guaranteed.
You could even move only 10" in turn 1 to allow for shooting as well - increases your maximum possible damage, risks preventing a turn 2 charge especially if they haven't deployed right on the line (you'll have minimum 14" charge, which is still well within expected normal charge range, but if it's not a perfect straight line and they've deployed a couple inches back it could easily be pushing up to your max declarable charge at 18" so situation dependent)
Against this allows you to take a couple chariots in deep on turn 1 without risk of being shot, for a turn 2 charge on critical targets. While this implies some deployment skill, if you e.g. had 5 skycutters in a SG army, the scouts deployment being last means actually it wouldn't be too hard
Scenario 3: Charge Options

The point of this one is to give them only bad movement options.
This one is the hardest to setup, least important and mostly irrelevant on skycutters because of flying. You could setup the Tiranoc unit just outside of charge range which reducing risk but the closer you are the more constrained they are.
The lopsided setup is important. If they charge the SW, they'll fire & flee (and recover with Feigned Flight) - between the wheel and the flee move there's a good chance that will fall short if they continue the charge (by choice or because they failed the leadership test). This can also move them away from e.g. your main force to the right and it sets up a flank charge from the chariots. If they redirect there's either a high chance of falling short (but note: this would be true if the SW weren't there either - you can setup at 16.5inches to prevent it as that's the maximum charge declare range).
If they opt not to charge they have worse maneuvering options because of the SW blocking certain paths - and likely anywhere they choose will setup for a flank charge from either SW or the chariots. The closer you are the more their options are blocked, but the higher risk of the charges. Regardless of choices and dice rolls your chariots should be able to charge on the next turn with no fear of being blocked.
This last one I've only used a few times, it's more just annoying to the opponent than it is awesome.