Existing part suggestions:
Boosters should give exocraft a speed boost as an alternative to instant traveling but the speed can be altered by a convenient slide bar so those who are made of engines are not zooming around making orbits whether they like it or not. It would also increase the value of pilot pods as an all-in-one part.
Drone bays should have a 3x3 option that can store 16 drones externally in a port-like fashion where the drones cannot be repaired past 75% health and can be targeted by guardians (but not locked onto by them because that's unfair) due to the fact that the drones are outside the exocraft, stuck to the bay. Also there should be a 4x drone bay.
Wing parts should improve maneuverability
4x parts should have various shapes similar to those in Tetris so players composed of 4x parts can be more than just a blob of squares.
Some miscellaneous parts should have more health and shield than normal so they can be used as shields.
There should be a 4x and a 9x pilot pod >:)

New part suggestions:
Shield: There are 2 types, physical shields and projectors. Physical shields are basically wing parts but square or shield shaped and have much more health and defense than wing parts. Projectors project a shield around a certain area (2x2, 3x3, 4x4, etc) and block all projectiles that touch it. They take a small (really small, like 1 crystal per 100 damage) crystal cost to charge, similar to the shielding technology found in pilot pods. Alternatively they could be charged from the hangar with credits (small price here too like 1 credit for 100 power and 1 power consumed per damage taken). However, the lifetime of the shield projector decreases at a constant rate and once it reaches 0, 1 elemental core must be spent to repair it (the part doesn't die, the projector does and stops working, after which the part DOES start to die because it takes damage).
Docking tube: These can be used to dock 2 or more exocraft together. With the new fleet feature, multiple exocraft can be deployed at the same time to make use of their combined firepower and storage. To use them between multiple players, click on the part then click on another player's tube module as if it was a part to pick up. A request to dock will appear on the target player's screen and if the player accepts, the autopilot will move the 2 players together and a tube will extend between the 2 craft. Control of the resulting craft should be shared or given to 1 player with a general consensus. The players still maintain control of their own cargo and crew to avoid theft. The tube cannot be attacked but the modules can be attacked by guardians and when broken will sever the link between 2 players but multiple links can be made with multiple tube modules once the initial request has been accepted. Pilot pods, while not being able to extend a docking tube, can attach to one to improve the new player experience (how would it feel to pilot the exocraft of #1 player on the leaderboard 5 minutes into the game?)
Mounted turret part: People have been talking about this for some time and I want to improve on it. They are smaller versions of the giant turret found in beacon bay and can be attached to exocraft like any other part(they are 4 sided squares). There are 3 types of turret you can buy (aqua, spark, and lava) and each has the same stats as a drone bay unless the guardian it is attacking is the guardian it is strong against (lava vs spark, aqua vs lava, spark vs aqua), then it has double stats or whatever multiplier drones have, whichever is greater or most balanced. They have a higher range than drones and auto-attack guardians (players can change this in settings) but they won't attack mines.