In the U.S. the maximum course change in RNAV procedures is 90 degrees, with a maximum of 70 degrees being the maximum optimum. Course changes from airways to ground based procedures can be up to 120 degrees. For course changes from airways onto RNAV procedures the limit is 90 degrees.
For radar vectors to the final approach course (usually an ILS) the controller is limited to a 30 degree intercept angle except within 2 miles of the "approach gate" where the angle is limited to 20 degrees.
For a procedures designer to avoid a procedure turn (or course reversal holding pattern) the intercept angle cannot exceed 90 degrees and descent gradient limits must be met. This would be at the intermediate fix, which is at least 6 miles from the FAF.