I see a few things i would change immediately without question. The receiver especially. You should just start with ELRS and use EP1 receiver. Also that receiver is way too bulky for a quad by todays standards. Secondly the Source One V4 has known issues such as the weak arms that break easily and resonation issues. The problem is fixed in the Source One V5 with thicker 6mm arms rather then the 4mm arms and a new center brace. Unfortunately RDQ hasn't updated theirs to V5 yet. I have a Foxeer Razer mini and is was kinda too dark and i couldn't adjust the settings so flew it like that for a while then upgraded to Caddx Ratel. Dramatically much much better picture for slight increase in price. I tried the Jhemcu VTX and i didn't like it. Had some weird issues, have two of them and both are wonky so I replaced with SpeedyBee TX800 which for $10 more is awesome. VTX antenna (2 pack) Make sure the polarity you chose matches your goggles (usually RHCP) You don't need a mmcx to SMA pigtail with these antennas.

Here are some Build supplies

Here is the bag I use to carry everything, carries 3 quads, 8 batteries, TX16S, Sky04X goggles, tools, spare props, misc items such as battery checker and spare zipties, screws etc. I like it as an everyday bag because it's compact so no need to lug around a massive bag just to go up to a spot to fly.

Also what u/simen64 said.

For goggles get the best one you can afford. EV800D is a favorite for low budget but Skyzone Cobra X is dramatically better. If you can get Sky04L or Sky04X then that's an option. The best option is HDZero with analog adapter. It just depends on you budget.

For Radio get any Radiomaster radio that supports ELRS. TX12 ELRS Zorro ELRS or TX16S ELRS for the most long term versatility. You can get the cheapest Radiomaster radio then put the savings towards better goggles.

Good luck.