Think it'd make sense to leave them in their spot on the curve and then ignore them for curve reasons?
Yeah. Realistically, expensive cycling cards are going to be used as cantrips more often than they are going to be cast, but the cast "mode" is relevant enough to make counting them as just their cycle cost inaccurate. They're almost like kicker cards in the sense that they can cost two mana, but people won't always cast them for two mana, like
Kavu Titan. There's just no perfect place to put these cards from a curve standpoint other than the broad category of "cantrip."
Unless something cycles for 3+, then maybe it should count as it's MV first and cycler second?
I think this is probably wise. Most decks are not going to want to pay 3 mana to simply draw a card if they can avoid it, even if that effect comes attached to a spell. Cycling
is basically a last resort to use an otherwise useless card unless it comes with a spell effect tacked on.
As long as I'm not way off the mark, I think that's what I'm most concerned about. It feels really weird to have FOUR 7+ drops in a single color.
Cycling cards just don't interact with the curve the same way most other cards will. The only "real" 7 drop in your selection above is
Akroma, Angel of Wrath, the rest are split cards with a 2 mana mode and a 7 mana mode. Even though these cards have cheap mana floors, they usually won't be used on curve, making their placement ultimately pretty meaningless outside of spreadsheet aesthetics. The important thing is that they can be utilized at any stage of the game and provide flexible options to players.
There is a point where you might have too many big cyclers: when player's can't meaningfully draft an intended density dependent archetype due to lack of proper support. For example, if you want a White aggressive deck to be a thing, if players have can't get more than three or four 1-drops (or more likely 2-drops in this case) on average, that deck isn't going to function. If this is because you're running to many random cycling cards, you're going to want to cut some of those and add back support for the intended other deck. I know that's not rocket science, but it is honestly the best barometer for "what is too much of thing X."
One thing I would worry about in your shoes is Morph Curve. I'm bringing this up because I looked at your Cube list and saw that Blue had a whopping 20 three drops when counting Morphs. Blue creatures make up roughly 25% of the Blue section at this point in the Cube's development, not counting other spells. Green, by contrast, only has 9. Having such a glut of 3 MV cards in Blue might make the color less viable than it's counterparts, simply because roughly 1/3rd of it's options are cards that want to be played for exactly 3 mana. It looks like a lot of your blue 3MV cards are fairly flexible due to cycling or morph, but it would still likely make the color smoother if hard 3-drops such as
vexing gull were removed from the Cube.