I would argue this is EA bias though. This balance between spell-attack vs. ST will flip back to ST/conc spells being stronger once higher spells kick in,
even with Larian's changes. There are 24 spell-attack spells in the Player's Handbook. Only 5 are 3rd level or above:
- Vampiric Touch
- Faithful Hound (summon - but uses your spell attack for melee)
- Contagon (touch, but requires save too)
- Dispel Good/Evil (touch for dismissal feature, but requires save)
- Mordakainen's Sword (summon - but uses your spell attack for melee)
Once level 5 kicks in and you get access to Slow, Fireball, Hypnotic Pattern, ST spells that are completely game changers.
Sure, 5th+ levels will make ST spells more viable as you get access to these strong spells like fireball, etc. Especially as cantrips like firebolt will be less useful, only dealing 2d6 damage instead of PnP's 2d10.
Though, warlocks will still be heavily incentivized to use eldritch blast given the ease of hitting due to high ground Advantage.
But it will still remain easy to fail concentration checks, against enemies that can shove you prone or cause AoE damage with special arrows/flasks. Being set on fire will ~equally disrupt conc at level 6 compared to level 4 and I assume the # of enemies with these options won't go down at higher levels...
