Honestly, I would be pretty happy with SS if it had 2 wards upon recall, but generated 1 per minute. You could recall for the instant refresh on the wards on it, but just being active in general would still get you 2 wards up 100% of the time, and 3 up 50% of the time. Have the RSS have the 4 ward stored cap, and the ward duration increased to 3 minutes (Meaning it grants 100% ward uptime, and the ability to refresh a ward to a new spot if you have to). The Eye-stones could all just have a 3 ward cap, and the 1 minute refresh. A small power increase in warding to upgrade to it, but if you want true vision dominance you need to go for the dedicated warding power of RSS. I still wouldn't want it to increase the sight ward cap (Maybe, if anything, let you drop one more pink ward down).
This makes RSS far more attractive with significantly increased ward limit/minor duration increase per recall, and it's a buff to SS and the Eye-stones for any duration of time past 1 minute from base, which is more than worth it. Generally if you didn't even get your 3 wards down within a minute anyway, it was because you were so under pressure from the enemy it doesn't really matter, and you are close enough to fountain to refresh the wards anyway.