Runes and a Discussion about HP runes

Before you reach level 20, you should have saved up some IP for runes. How much?

The highest possible amount that a full page of runes can set you back is 28290 IP.
The lowest possible amount that a full page of runes can set you back is 7080 IP.

The difference in IP is staggering, but how about the difference in statistics?

Here are the most expensive runes:
('Red' = Mark, 'Blue' = Glyph, 'Yellow' = Seal)


Red:

• Greater Mark of Fevor: +2.33% Critical Damage (x9 = +20.97% Critical Damage)
• Greater Mark of Vitality: +0.54 HP/level (x9 = +4.86 HP at Level 1, +87.48 at Level 18)

Blue:

• Greater Glyph of Acumen: +2.2 Energy (x9 = +19.8 Energy)
• Greater Glyph of Vitality: +0.54 HP/level (x9 = +4.86 HP at Level 1, +87.48 HP at Level 18)
• Greater Glyph of Focus: -0.65% Cooldowns (x9 = -5.85% cooldown time)
• Greater Glyph of Furor: +0.56% Critical Damage (x9 = +5.04% Critical Damage)
• Greater Glyph of Vigor: +0.27 HP Regen/5 sec (x9 = +2.43 HP Regen/5 sec)
• Greater Glyph of Sapience: +0.161 Energy/level (x9 = +1.449 Energy at Level 1, +26.1 Energy at Level 18)

Yellow:

• Greater Seal of Fortitude: +5.35 HP (x9 = +48.15 HP)
• Greater Seal of Evasion: +0.75% Dodge (x9 = +6.75% Dodge)
• Greater Seal of Lucidity: +0.064 Energy regen/5 sec per level (x9 = +0.576 Energy regen/5 sec at Level 1,  +10.35 Energy regen/5 sec at Level 18)
• Greater Seal of Meditation: +0.63 Energy regen/5 sec (x9 = +5.67 Energy regen/5 sec)
• Greater Seal of Furor: +0.78% Critical Damage (x9 = +7.02% Critical Damage)
• Greater Seal of Vigor: +0.43 HP regen/5 sec (x9 = +3.87 HP regen/5 sec)

Bolded entries are especially interesting. You can see with both Blue/Red Vitality runes, you get a bonus of 174.96 HP at Level 18, which is rather good. Combined with Flat HP Quintessences (+26 HP ea.), you get a final bonus of 252.96 HP at Level 18. (87.72 at Level 1).

Add in the Veteran's Scars defensive mastery (+48 HP if maxed, +12 per level), and you get

+300.96 HP at Level 18

+135.72 HP at Level 1

It's no coincidence that HP/level runes are among the most expensive. HP/Level runes are helpful for every single champion, but it's tanks that benefit from the extra beefiness at every level. Is Riot discouraging tanks from the metagame by putting a heavy pricetag on the runes? 

Well, at Level 1 Anivia has 420 HP. Using VS and the above runes, she gets approx. 555 HP, 33% more HP, an entire third more health!

At Level 18, 300 HP is about a fifth of Soraka's HP, but only an eighth of Alistar's Base HP. So is this meant of be for casters instead of tanks?

We have to then take a look at the CDR runes, a very popular choice among many mages (despite a rather low reduction of 5.85%, IMO). 

Assuming mages would choose CDR over HP, and magic penetration over HP, there's nothing left but HP Quints. Even the masteries for mages are usually Utility or Offensive.

So we're left with Support. It seems that Support characters, the ones that would benefit the most from this (such as Soraka) also have the most leeway with their runes (magic penetration isn't a must-have on most Support mages). 

It could also be that Riot is trying to avoid beefy games. By making HP runes less appealing, early game fights with squishy characters are over much faster.

Evasion runes are often used on Jax, but with Ninja Tabi you have about 18% dodge chance on ANY character (granted it's usually melee DPS which take those boots). Add in masteries for a 20% dodge chance.

So evasion runes are also a great choice, and with SoTD being used very little in lower ELO games, it's an expensive but possibly good rune choice - if you want to take your chances.