You probably should describe what you mean by better engine. Higher mpg, better longevity (247k is damn good, don't know how you'd improve upon that), more aftermarket support, more power/torque, etc.
If you want to continue to use the term "drop in" and mean it, better stick to an exact replacement for year and model. A switch to anything else would be a nice project, but most wouldn't be prepared for the time, cost, amount of fabrication, and how long the car is actually out of commission while you're working on a more elaborate swap.
If you're mainly looking for a bump in power, you can fabricate a turbo setup for the 1.9 Saturn motor for probably less time and $$ than it would be to fit in a motor trans combo from some other car. The guys who post on the forums at
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have done some amazing things withSaturn motors.
Lane [ lane (at) evilplastic.com ]