I'm curious about Warlock 2 vs Wizard 2.
4 adventuring days with even odds:
(1 fight)
(2 fights)
(1 fight, 1 short rest, 1 fight)
(2 fights, 1 short rest, 1 fight)
16 casting stat, 14 con, 14 dex
Level 2 Wizard.
14 HP
No armor (12 AC, or 15 if use Mage Armor)
3.5 1st level spell slots/day on average
5/8 prepared spells
3 cantrips
Rituals (for all 8 spells)
Expertise in 1 skill
At-Will damage: 6.5 (Toll the Bell)
Could swap 0.5 spells/day for a 1 hour delay at start of day to get mage armor+arcane recovery to get it back.
Level 2 Warlock
17 HP
Light armor (14 AC)
3.75 1st level spells/day on average (3/4 example days have a break long enough to recover a slot, 2/4 have a short rest)
3 invocations (Say: Agonizing Blast, Pact of the Tome, 1 other Invocation)
2+3(Tome) Cantrips
3 Warlock+2(Tome) any Rituals prepared spells
Ritual casting on 2(Tome) spells
At-Will damage: 8.5 (EB, 5.5 + Agonizing 3)
Can get Mage Armor, Fiendish Vigor, Devil's Sight, Mask of Many Faces, Misty Visions, or many other great utility Invocations. I think that beats out +2 in a skill. Being able to pick any 2 ritual tagged spells beats out Wizard rituals I think. You can cherry-pick any Ritual from any list and cast it using slots or over 10 minutes, which I think matches the Wizard "choose 5/8 each day" flexibility.
You have 3 more HP, and 2 more AC without mage armor. You have more 1st level slots over a typical adventuring day at 2nd level. Your at-will damage is higher. You have more cantrips from a wider selection.
The Wizard spell list is better than the Warlock one, on the other hand, even at 2nd level; I find it hard to find good Warlock spells even with the short number of spells known.