Assuming base accuracy of 70%, and sufficient targets to get max bounces at each spell level.
Innate Sorcery active.
Lvl Cast | Base Dmg | w/Empower | % Gain | w/Seeking | % Gain | w/Elven Acc | % Gain | w/Emp+Seek | % Gain |
---|
1 | 17.86 | 26.58 | 149% | 19.88 | 111% | 20.10 | 113% | 29.29 | 164% |
2 | 33.09 | 49.89 | 151% | 38.10 | 115% | 38.22 | 115% | 57.48 | 174% |
3 | 59.51 | 84.49 | 142% | 71.67 | 120% | 71.15 | 120% | 102.1 | 172% |
4 | 98.92 | 115.7 | 117% | 125.2 | 127% | 122.9 | 124% | 147.0 | 149% |
5 | 146.0 | 160.2 | 110% | 193.9 | 133% | 188.1 | 129% | 212.6 | 146% |
6 | 193.5 | 205.3 | 106% | 268.1 | 139% | 257.5 | 133% | 283.5 | 147% |
Empowered Spell is the best option for spell levels 1-3. Seeking Spell (or Elven Accuracy) is best for spell levels 4-6. The combination of the two is obviously stronger than each on their own, but I still wouldn't use the combo before spell level 4. The gain over Empowered Spell doesn't feel worth that metamagic slot.
Personally, I'd start off with Empowered Spell and Twin Spell, rather than Seeking Spell, because of Twin Spell's use for non-blaster utility. Pick up Seeking Spell at level 10. However if you don't care about utility at all, and you also expect it to be common to not have Innate Sorcery available, then Seeking Spell is a lot more useful.
I wouldn't bother with getting Hex for a CO build. It's +1d6 against a single target (so irrelevant for all bounce targets), and uses concentration. Plus it's a bonus action to cast, so if you don't have it pre-cast, you have to wait a turn so that you can get Innate Sorcery active first. And even if you
did have it pre-cast, it might very well need that bonus action to move it onto a target creature, so once again you'd have to wait til the turn after you activated Innate Sorcery. It might be more useful for a Scorching Ray build.
For Fireball, assuming the same number of targets hit as Chromatic Orb, +3 Dex save, and optional use of Empowered Spell:
Level Cast | Fireball | w/Empower | % Gain |
---|
1 | 0.00 | 0.00 | 0% |
2 | 0.00 | 0.00 | 0% |
3 | 95.20 | 115.60 | 121% |
4 | 133.88 | 159.38 | 119% |
5 | 178.50 | 216.75 | 121% |
6 | 229.08 | 273.70 | 119% |