I apologize right off; I feel dumber than a bag of rocks and need help badly!
So I am looking for confirmation about effective "caster levels" by taking the Epic Feat Master of Light as a pure AoV caster.
Master of Light: gain 10 Maximum Caster Levels [MCL] for Searing Light / Sun Bolt / Divine Punishment
Searing Light: standard MCL = 10
Sun Bolt: standard MCL = 15
Divine Punishment: standard MCL = 20
AoV provides +1 Caster Level [CL] and +2 Maximum Caster Levels for each of these 3 spells per Core; +6 CL and +12 MCL at level 20
AoV also can provide another +3 CL and +3 MCL at tiers 4 and 5 [for all Fire, Force, Light and Physical Damage spells]
10 Epic Levels provide a further +5 CL and +5 MCL
*** My assumption is that Epic Levels do not count towards an FvS's Caster Levels ***
At Level 30, AoV Cap and optional +3 CL and +3 MCL from AoV
- Searing Light: MCL = 10+12+3+5 = 30; CL = 20+6+3+5 = 34 [CL - MCL = 4 "potential DPS increase"]
- Sun Bolt: MCL = 15+12+3+5 = 35; CL = 34 [CL - MCL = -1 "no potential DPS increase"]
- Divine Punishment: MCL = 20 + 20 = 40; CL = 34 [CL - MCL = -6 "no potential DPS increase"]
With a Divine Augmentation IX item [+2 CL] then Searing Light would benefit from +6 effective CL by taking the Master of Light feat, Sun Bolt would benefit from +1 CL, but [and here comes the part where I am scratching my head] Divine Punishment's damage would remain unaltered. Without such an item [Divine Augmentation IX] then only Searing Light would gain +4 CL by taking the [Master of Light] feat.
Conclusion: taking Master of Light with an FvS/AoH build does NOT increase the damage of all three associated spells...
(1) Without a Divine Augmentation IX item:
Searing Light effectively gains +4 MCL for a +13.33% damage increase;
Sun Bolt damage remains unchanged, and
Divine Punishment damage also remains unchanged.
(2) WITH a Divine Augmentation IX item:
Searing Light effectively gains +6 MCL for a +20% damage increase;
Sun Bolt effectively gains +1 MCL for a +2.857% damage increase, and
Divine Punishment damage remains unchanged.
So by taking the Master of Light Feat, the only spell that will have it's damage noticebly increased, even with a Divine Augmentation IX item, [+1/35th isn't really worth mentioning] would be Searing Light.
NOTE: I am leaning towards opting for the Master of Alignment Feat, which includes Holy Smite; this spell also has a standard MCL of 10 but is uneffected by the AoV cores, so at level 30, it's upgraded MCL would become 10+10+3+5 = 28 and it's CL would be 20+3+5 = 28 too. BINGO! Holy Smite has a Will save for half damage and the blindness effect, so in my eyes it could be a useful AoE spell at end game [with the additional 10 MCL].
Please advise if I have missed something fundamental. Thanks!