Just wanted to drop in and mention that
edshipyard.com now supports engineer modifications, so you can experiment with various modifiers to see how they impact your overall loadout.
It also now supports importing from the Companion API, so if anyone here has their API export showing modified modules, please try loading it (copy-paste into the import box, or just drag-drop the JSON file onto the page). If you get a popup about unknown modifications, I'd love it if you could send me a copy of that JSON file along with screenshots of the "MODIFICATIONS" view of the modified modules in the in-game outfitter (showing their modified attribute values) so I can add support for more modifier types. Thanks!