Regarding the type rating in helicopters bit:
Paraphrased from the OLD FAR 61.31(a): A type rating is required when a helicopter is used in operations requiring an airline transport pilot certificate.
Thus, if you used a Bell Jet Ranger in on-demand 135 ops, then no type rating needed. If you used it in Part 121 ops (for example), then you DID need a type rating.
It had nothing to do with demonstrating IFR proficiency in a particular type. An IFR ticket is (and was) as good in one helicopter as the other.
Under these rules, the FAA (or DE) would automatically type rate you in what ever helicopter you took your ATP ride in, and many would give a type if you took a part 135 check if you demonstrated IFR compentency.
It should be noted that you CAN take an IFR checkride in a helicopter that is not certified for IFR flight, as long as it has sufficient equipment for all the areas of operations. Unless the helicopter is certified for single pilot IFR (expensive), the examiner will act as a co-pilot. If you couldn't do all the areas of operations requred for IFR in a particluar type, then you got the VFR restriction.
I did my ATP - Heilo in a Robinson R-22. I got the type with the ATP. Probably one of the lowest grossing types out there (1370 LBS).
The FAA changed the reg some years ago to eliminate this requirement, but you get to keep your type. Same as when they instituted the 50 NM x-country rule for the ATP. Those that logged XC from one airport to the next, even if it was 5 NM apart, got to log it towards their ATP XC requirement.
Lots of rule changes over the years. I remember when you had to have 200 hours for the instrument ticket.
Nu