Perhaps a revolution in electronics, allowing for safer if not nearly autonomous landings.

Well, you touched on most of the ones I have in mind, but here's what I see:

As you say, UCAVs and the associated automated landing technologies are one big part of it.  They've tested this with both V/STOL (QuinetiQ with their VAAC Harrier) and with CTOL aircraft (a F/A-18A using the Shipboard Relative GPS System).  This will allow both safe UCAV operations and safer manned aircraft operations -- there's no reason you can't fit a UCAV-style landing system in a manned aircraft.  As it is now, most carrier landings are performed with the throttle controlled automatically, this lets the computer fly the ball as well.

Another is the reduction on the reliance on steam in flight deck systems.  The steam-powered catapult is replaced by an electromagnetic aircraft launching system (EMALS), which uses only electric power.  This gets rid of the complex, bulky, and maintenance intensive steam transmission and storage systems, and allows more reduncancy (i.e. you don't absolutely have to power the catapults from the ship's main engines).  Although I don't really support the idea of smaller carriers, this will allow them to be more practical since there is much less volume and manpower required for catapults.

the size, shape, lift and PERFORMANCE of aircraft.

That drives the SIZE of a port avions.

What you want to do today DEFENSIVELY even with  jet propelled UCAVs is not possible unless you build to Illustrious size.

OFFENSE requires twice the size.

An air defense ship is a joke, unless you have an offensive option. India chooses to use a Brahmos solution. The US chooses to reach farther with air launched  munitions so we build to the requirement.

Poseurs who keep wishing they can build small carriers to do what a Nimitz or to a lesser extent what a QE will do simply refuse to accept the engineering limitations that  Bernoulli imposes  on us all.

The Indian Navy, being honest call their ships what they are, likewise did the Russian Navy.

Herald

I've got one for you - not sure what the proper terminology would be - but how about a blown deck? 

As STOBAR decks are passively ventilated to dissipate VTOL exhaust and to provide optimal ground effect, take your flight deck and actively vent it.  It would increase or decrease nominal airspeed as desired, for takeoffs and landings alike.  And perhaps it would be easier to create a 40kt air current with fans, than it would be to build a 40kt hull design.  Combining both, of course, you would have 80kt headwinds and practically be able to boost a Cessna right off the deck, let alone increase MTOW, range, payload, etc., for CTOL/CATO types.  Reduce T/L distances for smaller carriers, perhaps?

You would want to be able to vent in different directions; fore/aft at least, with mixed horizontal/vertical components and variable force.  I suppose there might be some benefit in creating negative pressure (i.e. vacuum, i.e. sucking not blowing); perhaps it would land/stop planes faster.

Given a highly granular (multizone) structure, and incorporation of flame retardants, it might be used to extinguish fires on deck.

OTOH, the deck would no longer be solid but a grating like that over a subway vent on the sidewalk.  Weather might affect the system adversely.  FOD risk might be either increased or reduced.  Girls' skirts would go all Marilyn Monroe. 

I'm going to take a WAG, based on size and cost of Patton room fans (not recommended method!), and suggest this might cost $50M to implement for a Nimitz-sized deck.  More if retrofitted, no doubt.  This might be mitigated in several ways, e.g., by not blowing whole deck.

1. Topweight.
2. Can't possibly funnel the effect in the desired vector.
3. Coriolis effect.
4. Doubling the CV wattage output that you require for the projected use of a super wind curtain is not efficient. You can use that additional electricity better in radars or electronic warfare systems, or a catapult  or even a DEW.

Herald