Hmmm. Agreed, that system is quite flexible but also prone to complicate things up. Because every action will take many turns having a full day lasting 86400 turns for a 24 hours day of course.
Let's assume I order my party to build a shelter in the woods and that this requires finding a suitable spot, cutting trees down, creating timber and finally putting everything together, this could probably require a full day of work or lets say 53000 turns.
Now let's assume the player casts a spell having the following description: "Increases the party's critical chance during combat by 10%. Duration: 7200 turns (2 hours)
Even small actions like eating an apple could take 300 turns which I think can be a bit overwhelming for the player to interpretate. I could always say 5 minutes but 5min doesn't tell how many turns it is. Worst case scenario: 5min (300 turns).
Of course I'm injecting your system directly into my game's game play mechanics. It doesn't mean it won't function in yours. I think I will keep a full day to something like 1000-3000 turns. This will mean some actions happening in slow-motion but a better overall interpretation of time. At least this is what I think.