We're with you on the concept that leveling to 30's too long a process and the total number of games needed to get there should be lowered. Tying quicker progress to the first win of the day bonus results in people that only play a small to moderate amount getting to 30 in noticeably fewer games played than people who are playing a lot though. That's generally the opposite of what's desirable (people playing their games in a concentrated window will tend to pick things up quicker and be more ready to hit 30 rather than less).
What we're going to do instead, probably in the next patch, is lower the total amount of XP needed to get to 30 by around half. That's an approach we investigated using the Russian LoL server as a test case last year as some people may recall. The results of that test looked positive, so we've polished the details a bit, in particular smoothing out some sudden large increases in XP needed at certain levels, and are now ready to apply those changes to all regions.