i cannot see f1 or fans buying a full-course yellow for every little thing.
I don't think you need them in "normal conditions". But if you have changing conditions, sudden surface changes, you should get the safety car out. And even that doesn't always help, as we've seen this weekend.
Implementing fixed pit-limiter speed limits in double-yellow sectors would be another option, one step short of a full course caution, but the tires cooling down would in itself present a hazard.
I think what needs to be reviewed is when safety cars are called, and when they are not, and a ruling has to be agreed upon. Having this be up to the race director on a case-by-case basis is probably not a good idea (but he should be able to override the rulings in favor of a safety car)
Safety cars should also be made less invasive. Instead of allowing everyone to unlap themselves, lapped cars should filter back until there is a gap between leading-lap cars that exceeded five seconds before the full course caution. That way they're not in the way of the previous battles, but don't have to race around a circuit that is under caution either, or move very far at all. Clearing Sutil's car would have probably taken a single safety car lap (+out and in) to be finished. It would also have allowed the teams to switch to wet tires, given the potential for aquaplaning.
Skirts on the recovery vehicles also wouldn't be too awkward, but as pointed out, stewards would still be exposed.
As I said in an earlier post, for each circuit, each corner, clear safety car deployment rules have to be laid out, and followed. In Silverstone the race was red-flagged because some armco along a straight was damaged. Here, the safety car was not deployed, despite a similarly grave reduction in track limit safety, and much worse driving conditions. These inconsistencies have to be resolved.
Maybe medium sized mobile cranes should be used, which can be parked behind the tire barrier, and have enough reach to get to any car that made it as far as the barrier, with minimal exposure of stewards to recover the vehicle. This would be logistically easier than using big cranes everywhere, and these vehicles would not be significantly less mobile than the currently used tractors. Also, accidents such as the one in Montreal in 2013 can be avoided by using cranes that lift the vehicles across the barriers, as opposed to towing them out, going backwards.
There are a number of options to increase safety, and I don't think the FIA can afford not to do anything about these dangerous situations, since this type of accident is striking from time to time, and can be mitigated relatively easily. It's just tragic, that it took an accident of this magnitude (especially given Brundle's experience 20 years ago, and the Canada accident) to review the procedures for recovery of crashed cars.