Riot doesn't even need to worry about the $$. They hit their peak of players back in 2013-2014 and a good multitude left out of frustration. My dad always said if you really want something, you keep on trying until you get it.
I don't want new players to get everything for free, but if even if no new champions came out, and all the benefits were given to new players from OP's post, they would get 30,000 IP at level 30 and about 6 free Champions.
Now, I love the idea of the chest system... but it doesn't benefit new players. Especially when smurfs enter the equation. I'm shocked at the thought new players only get either a Garen or an Ashe for free. Garen, Alister, and Tristana are all free for subscribing (for free) to Twitter, Facebook, and Youtube (respectably). Why not just make publicize this better? And while their at it, how about a free champion that's 4800 (or higher), or if they are feeling generous they can say 6300 or higher.
A new player would still only get (at most) get the three mentioned for free, plus the other 6 per every 5 levels, and then (maybe at a rough estimate) 10: 450 Champions and 22: 1350 Champions (and this is just a speculation) which totals to about a good 39 out of the 133 Champions in the game. You would still have 94 to go... but lets not end there, you did reach level 30 so by that time you should have been able to get around 20-40 Champions on your own. So that brings it down to still 74-54 Champions (and I'm being fair by still going by the cheapest Champions in game). In order to get the other 74-54 Champions, you would need to play for pretty much the whole next year.
A lot of veterans forget that they had it easier when the most a Champion cost in the past was 4800 but now they cost 6300 (a whole 1500 more).
I can't say it would be perfect, but bringing a number of 133 down to 74 or 54 would make things a lot easier.
And then there's the obvious teir 1 Runes should all be free. (Or at least most of them.)