While using the straddleboard you can double jump. Without any enchantments you can only extend the normal jump but with straddle jump 3? Oh boy that board can go high and far. If jumping while in the air was removed it would probably work fine.
https://cdn.discordapp.com/attachments/774495815262535701/835931839557533736/Flying.mp4 video of how high you can go
https://cdn.discordapp.com/attachments/774495815262535701/835933034124673034/BalancedMechanic.mp4 video of how far you can go in distance. All of this works in survival mode too.