Check compatibility here:
[Link: support.myharmony.com]

The Elite is probably the closest. It is a big step down in many respects (only has 15 devices instead of 255, no variables, no pronto hex import, etc.). But is a big step up in others (smartphone integration, broader home automation support, IP and BT control, simpler programming).

You will have to start form scratch.

You can program it yourself with freely available software, or hire someone else to do it.

I recommend you buy an Elite to try. If it doesn't work out, return it, and hire that electrician.