I think rather than comparing IO to RA, we should be looking at the Demo Rules for RA vs the full rules for RA.
Demo rules didn't remove more mechanics than SSRs and construction rules. Cover, range, double-systems, et cetera are all a distinct and important parts of showing the flexibility of the system, otherwise you're simply playing chess with dice.
My recommendation is the diversify the builds a bit more, leave obstacles in, and allow each player access to an Ace. Aces are HUGELY important to IO, maybe even more-so than the loadout of any other single ship. More than once, I've heard the recommendation that your fleet construction should be influenced by the role and tactics that your Ace and squadrons will play.
Also, the comparison would more likely be X-wing to Armada, but that's nitpicking.