An interesting question, and so far I think the best answers have been of the 'who will be using it, and with what training?' kind. I would like to add 'what sort of injuries anticipated?'.
Useful things to have :
Gauze bandages plus some means of stopping bleeding - most likely woodworking injury
Sterile water/saline for eye washout, frankly, in a first aid situation tap water will be clean enough to wash out wounds - certainly cleaner than your skin or anything contaminating it. And you would need considerably more water to effectively wash out with than any you would put in a kit.
Elastoplast (or similar) to hold small wounds together - don't bother with steri-strips, they are fiddly and not necessary for first aid.
Medical tape is handy, but Elastoplast better than micropore for adhesion to skin, no need to have more than one type
Antiseptic is fine, if you have space
Fine tweezers and magnifying glass good ideas for splinterectomy
Printed phone list of people to call in an emergency
Probably a few other things I have forgotten, but the above would suit most situations.
Things I wouldn't bother including :
Any drugs whatsoever - if the injury is severe enough to warrant hospital admission, it might muck things up a little, and if it doesn't require professional help, then painkillers etc can be taken from home medicines.
Any duplication - keep things simple, in an emergency you want as few options presented to you as is reasonable. By all means have a stash of sticky plasters etc, but no need to have three types of tape, two type of bandage...
Anything requiring 'advanced' training - it might not be you who is using the kit
Just my thoughts...
KevM - your replies suggest you have experience here, may I ask whereabouts, and what is an Israeli field dressing? The clingfilm is also a very good idea, for the reasons you mention.
Cheers,
Adam