My last Porsche was a 1978 SC. I had it for 5-6 years. Went from Bone stock to track demon. I now have a 2000 Boxster. Night and day difference, so far all for the better. Love the "modern" features (A/C, Heat), like the ABS, Airbags too. Love having a mid engine car again (my first car was a 914) and the convertible is fantastic! I really like the sound, especially above 3k rpm. Test drive a few Boxsters. They are great cars.
Don't be afraid of the OBDII stuff. The RMS stuff, The coolant tank issues, Slipped sleeved cylinders. Blah blah. The list is endless. However, as the owner of a maligned 2.7l 911, you too know that the web can overhype any problem and that there are "good" ones out there
As to your '74, what do you mean by "restoration" Are we talking a guess of $5000 to be spent? $10,000? More? Who would do it? How long would it realistically take? While "rare", the US 1974 Carerra is not as special or unique as the Euro carerra with the high compression 2.7l MFI motors. The US ones are more like a trim package than a better performing car.