Honestly for a first hack it is not too bad however there are a good couple bugs and issues that need fixing before this hack can accepted.
Starting off the hack has a lot of cut-off. One of the main reasons is the usage of the Growing Vines which cut through a lot of the different environments.
In later levels we see Sprite Slowdown due to the amount of sprites on screen. This is an easy fix and can be avoided with proper testing and playing of levels before you submit them in a hack.
Silent Bullet Bills also make an appearance. They are an unfair hazard due to their speed and them having no SFX to warn the player. I do believe there is a patch you can use that adds SFX to these sprites to help solve the issue.
There are also a few instances of more easy to fix errors such as Sprite Tile Limits with rotating platforms as well as fixing Layer 3 tides that follow the player instead of staying in a set position.
The first castle is where the hack becomes unbeatable.
The castle features cut-off with the player been able to go past the end pipe into an unfinished area as well as a glitch when hitting a Bowser Statue while been beneath a Turn Block. You get forced into the wall and crushed.
The hack becomes unbeatable due to the final room with the Goal Sphere as walking into it makes Mario walk into the pit. In Vertical Levels Mario will stay still however in Horizontal Levels he'll walk as if he touched a Goal Post.
I had a look also in Lunar Magic and saw the same issues mentioned in a handful of other levels. I'd use this opportunity to fixed the mentioned issues but also fix other potential cut-off and glitches in the levels that I could not access.
As far as first hacks go this one was actually quite good. The level design is a tad basic but there is nothing too wrong with that.
I hope you can fix up these issues and that the hack hopefully gets accepted in the future.
The Castle Goal Sphere issue is still in the game as well as all of the other issues mentioned including Sprites & Cut-Off.
Please actually fix and address the issues mentioned previously before re-submitting.
Consider this a warning as if you submit the hack again with no changes or fixes it will result in a Section Ban.