so I can finally play ranked
I don't care if you've been playing for 2 years or not, but if you've only played enough games to be level 27 you aren't ready for ranked. Ranked isn't meant for the overly casual players. It's meant for competitive play and in order to do well you want to understand how all of the champions work (on the current patch) you want to be able to play a multitude of different champions/roles adequately (on the current patch), you want to have a few rune pages finished for at the bare minimum AP/AD/Tank champions, you want to know the lane match ups of your mains very well. Those lane match ups change over time as the champions change. If you've played so infrequently over 2 years that you aren't level 30 yet then you are definitely not ready for ranked. Draft pick is pretty much the same thing for casuals. Play draft instead of dragging your teammates down by prematurely hitting 30 (which is what an XP boost does) and then going straight into ranked.