Is 38 levels too much to unlock a rune page?
With the new blue essence it takes 30 levels with good rng to be able to afford a single rune page.
Which is about 300 games, without buying a single champion, and will take longer the higher level you are.
If you wanted to fill out all 20 rune pages it would cost 94,500 blue essence - 450 levels - which would be about 4,500 games
This is ontop of the crazy high cost of champions now
Current cost for all champions: 538,350 BE
Current BE gain: 910 non milestone level average then 2120 average every 10 levels
Only using champion shards to buy champs
Only buying champs you have the shard for decreases the total cost by 40% to 323,010 BE. You will have lost the 20% disenchant BE from the shards you didn't disenchant adding 107,670 BE. Grand total of 430,680 BE. Using max BE gain (perfect capsule every capsule) you gain 13,380 BE every 10 levels 430,680/13,380x10=Level 322 (This would require you get 1 of each champion shard then only 6300 champs in capsules, which to say the least would be a statistical anomaly) Using average BE gain values above you gain on average 10,310 BE every 10 levels 430,680/10,310x10= Level 418 AVERAGE This of course is assuming you get one shard for each champion in the 322/418 capsules you will have received.
Choosing the order that you buy champs
Buying champs from the store requires the full 583,350 Max BE gain: 538,350/13,380x10= Level 403 Average BE gain: 538,350/10,310x10= Level 523