I agree. In fact, if you don't need at least 3 PowerCells, an inMotion controller, and some custom programming, I'd stay with a traditional system.
Here's a few things I did with the ISIS kit that aren't that obvious:
1. I turn off all non-essential devices while engine is cranking. Windows, wipers, stereo, cooling fans, A/C, headlights, etc. All off. The only thing that gets juice is the starter, injectors, coils, ECM, TCU, and fuel pump.
2. The headlights, cooling fans, and fuel pump "soft" start. That will lengthen their lifespan and reduce the current in-rush. You can now run smaller, higher gauge wire, and numerically smaller fuses.
3. All essential engine circuits are integrated with security. No key fob, no hot wire. (thieves will probably just use a rollback, but still
)
4. I replaced the DSE RS headlight controller with custom ISIS programming.
5. Ever wired interior lights? Three switches (2 in the doors, one in the headlight switch). 14g wires going everywhere -- to the switches and to the lamps. With ISIS, you have a device circuit with a single wire going to each lamp (wired in series with a ground at each lamp), and a separate 28g wire for each switch.
6. Power window are a dream to wire. Two current-carrying wires to each window. In a whole separate circuit using 28g wire, the switches are connected to the MasterCell. Every single power window has one touch down.
Anyway... I'll stop now. It's not so much about the "features", it's more about the flexibility and configurability of the system.
Hope that's useful!