if you have an 01 with an h22a1, the last owner already blew the first engine that was in there. there really isnt a better engine to swap in, but you can build up your current engine.
for an insane n/a build, you can get some jdm h22 type-s pistons, drop down to a single layer head gasket, go with some big cams and a port and polish. After that, tune and complete.