There's no replacement for displacement, that saying came around for a reason. If you really want to blow a wad of cash worth more than your 98 neon, then swap the 2.4. Once its in your going to see more results from the mods than you would on the 2.0. It WILL make more power, the smaller motor just doesnt have the capacity. Sure you can boost the shit out of the 2.0 but your going to fry your internals.

Like you said on the SOHC... dont waste your money