There are then large signs at every exit on the roundabout.
Sometimes (not here) the approach lanes have giant letters/numbers painted in each lane, even if it's crushed so Warwick is written "Wa'ck" or something.
Nothing prevents you going around a second time if you need to. Your satnav will have said something like "In 500m, at the roundabout, take the second exit to Warwick" and then "Take the second exit to Warwick".
On this road (which is typical) there's the confirmation-of-route sign very soon after exiting the roundabout towards Warwick, or (third exit) to the village.
> you can just go around again if you aren't sure which exit you need; you are forced into taking an exit, right or wrong
...doesn't make sense?
> the radius is too small so there is not much time to make a complex decision, especially if you aren't already familiar with the exits
Ideally, you should know what exit you need from the signs you saw approaching the roundabout. If not, slow down and go around again.
> it's hard to monitor traffic entering the roundabout to make sure I don't get hit by someone having a harder time navigating this than me, while at the same time trying to figure out what the crazy sign diagrams mean.
This is why the signs were 100-200m before the roundabout. It sounds like you are approaching the roundabout too fast.
[1] https://www.google.com/maps/@52.1980889,-1.6002025,3a,75y,23...