No it is not. But if you think they are too similar it would be better, IMO, to revise other aspects of Combat Clarity or Doom Sense. Adding force damage it clunky and doesn't follow the design intent, as you describe it, IMO.
Combat clarity gives one person advantage on all attacks rolls, and as a reaction can cause one successful attack to become a critical hit, ending the spell. The only thing it doesn't do that you suggest for Doomsight is give max damage. And personally, I don't think that would be a balanced option for one damage dealing effect every round to deal max damage. This would become especially problematic based on the wording of the spell. The spell is specifically worded so that it is not limited to weapon attacks, but any time a target within range takes damage. Since the wording (and my personal intent) could be used on the target of a fireball, target of a divine smite, or target of a sneak attack, that would be incredibly powerful for a 3rd level spell. Maybe your table is different, but it wouldn't work for mine.
After your description of the design intent, the best option, IMO, is to leave the damage type up to the DM.
Sorry, but once again, I disagree. When a player uses an ability, they should have control over how it works and functions. The outcome and consequences are left to the dice and the DM, but a player should know upfront what kind of damage their spell is going to deal. For me and the way I perceive the game (which seems to be different than you), force damage is most likely to be invisible, least likely to be resisted or reduced by the enemies abilities, and is the most... I guess the best word is maybe sanitized of all the damage types. Each damage type implies a kind of source or after effect. For me, force is ephemeral, hard to define, and just generally more clean than any of the others. So I personally believe it works best for when instances of fate and chance cause some kind of damage. And yes, while you may not feel like it fits to add damage, I do feel it is appropriate.
Your disregard for the importance of damage type is very vexing to me. Not only does damage type have mechanical implications, but story implications too. I just think the force damage is not telling the story you say you want to tell. But I appreciate the effort as you made a decent chassis that I can modify easily for my game. Thank you!
While damage type
can have mechanical implications, that is only if the DM
strictly follows monster stat blocks. Personally, I have found it fun to adjust monsters and stat blocks to keep players to keep them on their toes and avoid them from metagaming, as well as to increase the challenge for my players. So from this style of play, yes, mechanically every damage type is just as good as every other damage type (and thus interchangeable). While monsters as presented in the Monster Manual and other sources may be more likely to have particular resistances or vulnerabilities, my play style means that a player is equally likely to encounter any of the various possible combinations of damage vulnerability or resistance.
And yes, as you say, damage types do assist in telling a story. And as I see it and for what force damage represents for me, it is as close as you can get in 5e as an untyped damage which fits perfectly for the effect and the story of how these spells work in my mind. Because yes, while in the example I provided using multiple damage types to represent the puncture, burn, and fall might fit, the point is that the actual kind of damage taken and the effect is actually greater than one might expect from that unfortunate series of events. The outcome is in fact greater than the sum of those parts, and in my mind's eye, force damage best captures that.
But, it seems like while we might have some philosophical differences or some differences in play style, it seems we generally agree that the structure and the mechanics are largely sound for the given level of the spells and within the paradigm set by 5e rules. So... I'll count that as a win.
