Eventually you will opt back to the beauty, simplicity and originality of the A series.
The e series is nice but although you can solve the dizzie problem with ecu ignition the
water passage to the back of the head is not aesthetically pleasing or rather ugly.
Since the bolt up is similar to a qg18de or ga16de you might find them better again
if going the e15 path. In Canada and Europe there is a ga16e with 12 valve head that
is supposed to be a midrange king with fat torque and great economy.
Very compact 12v sohc head design and it bolts up to the 1.8 liter gq18de block.
http://www.nissanforums.com/b11-b12-k ... eurocam-install-here.html

After many years the best bet is a boosted SU setup A series similar to Topgear
but with proper carbon sealed turbo, meth/water injection, jet coated exhaust
and adjustable in cabin boost controller for the feel/power you desire.
All using stock A12 with a14 crank, e15et pistons and a12a conrods.