I'd say you'll be looking at around 9-10kg on-ride weight for a lighter road bike & 2-3kg more for an aero bike. My town hack weights in at 7.9kg, that's a minimal fixed gear bike, add 2.5-3.5kg for gears, bottle holders, water, etc.
Lightness feels fast, aero is fast. As long as your speed remains above ~10mph. Aero typically adds weight to the bike. For this reason quite often a bike at £3000 will be heaver than one at £1500, just a lot more aero.
Contrary to popular belief rolling weight has very little impact on you performance. It does however change the way you need to ride to get the most performance out of your bike. The heaver your wheels the more power you expend accelerating, as such heavy wheels aren't great for group racing where there are rapid changes in pace. They are however great in TTs where you can maintain a steady pace for long periods. It takes more discipline to maximise the performance of heavy wheels.