Howdy,
This is highly dependant on how your team operates. Personally, you will be looking at around $3-4k per robot, so given the price I would actually advise getting your team a couple of Bambu Lab 3D printers, a Fusion 360 License, and to either use a pre-made VEX Fusion 360 Library that can be found here: VEX CAD Fusion 360 Parts Library 2.0.0 Release
In addition, in VEXU essentially all VEX Pro products (excluding electronics) are competition legal in VEXU so you can search the site there for cool verahub wheels or metal frames too: Home - VEX Robotics
Additionally, pneumatics are fair game too. As long as it conects to the original VEX solenoids, you can you any type of pneumatic cylinders, fittings, etc. An example order form can be found: Pneumatics | Purdue SIGBots Wiki
I would highly suggest looking at this wiki to start off learning about VEX: https://wiki.purduesigbots.com/
As a VEXU team, I would strongly encourage to download CAD models for the season and developing the robot in Fusion 360 or some other CAD software, and develop your robot in the CAD software before actually ordering components. However, getting a super kit first helps get a first general understanding or foundation on how to start understanding the patterns of how to build a VEX Robot and its limitations.
On another note
Because you are a new team, programming has its sophistications too but thats for another day
A bit off-topic but if you need a good coding foundation you will have PROS and VEXCode. As a VEXU team I would highly encourage PROS. The coding community in VEXU primarily uses PROS because of its professionalism and depots, however I myself find myself more comfortable with VEXCode as I feel like it’s closer to the hardware on a software standpoint. So coding is fundamentally something your team can choose or switch over time.
PROS First Time Users Guide — PROS for V5 3.8.0 documentation
A well-supported community-driven library LemLib for PROS can be found here:
LemLib documentation
If your team plans to use VEXCode, I would recommend JAR template:
About JAR Template | JAR-Template
I have also made my own library, WhoopLib, that works for PROS and VEXCode, if you would like to start understanding and open doors to more fundamentally complex coding:
My tutorial for coding your own PID for beginners: VEXCode PID Tutorial