One of the most recurring complaints as well as questions from new players is about obtaining weapons or finding a specific armament for their ship and it is an opinion I share. It is a bit difficult and tedious to fly around many sectors and star systems just to find a specific weapon and additionally for newer players give them a skewed experience on how many weapons there are or able to know more about the game's mechanics extensively. Not to mention the commission and military market mechanics which make obtaining the weapons you seek extra tedious since increasing one's reputation to a specific faction except for independents is very difficult and time-consuming.
My suggestion to fix this issue is to have markets of bigger factions such as Diktat, Tri-tachyon, and Hegemony to sell all of their available weapons. For example Sindria Diktat markets will sell all types of missiles of common type(maybe only military markets but with no commission/reputation prerequisite), Hegemony for ballistic and tri-tachyon for energy.
Alternatively maybe giving the player an option to order weapons from bar to an always available option by contacting the quartermaster of the said market as long as the player's reputation of said faction is neutral or above. I'm aware the player can do something similar currently by contacting a contact that sells weapon however it is locked behind a wall of rng and can lead to frustration if the player has bad rng or wishing to do specific role-playing playthrough.