2GR is superior, but around 3-4x more expensive, and your limited to using the stock ECU unless you want to spend $2000+ for an aftermarket ECU to handle the quad VVT.
The 1MZ however, you can by a whole Camry for $500 - $1000, and you can run it on a <$1000 aftermarket computer (Or a $300 MegaSquirt2) if your chasing more power over the stock ECU.
1MZ into an SW20 is fairly easy as it uses 3 out of 4 stock mounts, and the 4th mount (timing belt side) can be purchases for ~$120 from the UK. You can use either the S54 gearbox from the NA and matching drive shafts, or you can run the E153 with supported shafts. Flywheel is the only complication in that mix, where you can either run a modified 3SGTE flywheel or purchase either a factory 1MZFE manual flywheel or buy a Fidanza 1MZFE flywheel (4.5kg).
This would give you a bump to ~150RWHP in NA form, which is a big improvement on stock 3SGE and close to Gen1/2 3SGTE.
Add some boost with a GT35 or bigger turbo and you'll push up to 300+RWHP** where the pistons will start to fail (ring lands crack).
Replace the pistons with some forged jobbies, then you can push to 500+RWHP** where the rods will start to fail (block punching goodness).
Replace the rods and you can go higher again. I believe WTFAuto has the record of most power out of a 1MZFE at the moment at over 600RWHP, this was all on a stock crank, stock heads and ignition system.
** This is information based on what WTFAuto pioneered with their 1MZFE builds