Thanks for all the Input. As for the vLan 1 and Bridge:
I always thought the main reason to change from VLAN 1 would be security reasons, so I did not bother to (shame on me, I know....) but since the bridge is always VLAN 1, I am suggesting some kind of "loop" in lack of a better expression here that might make take packets some extra rounds, if I get it right. I created the interface for vlan one jusdt for the same reasons as I created the interfaces for the other vlans and put the bridge to it. Almost any tutorial on creating VLANs always told me: create the vlan as interface and then add the bridge. True, with vlan 1, this is kind of "extra". As for "why has the bridge an IP address?" Well, this was for it being used as IGMP querrier for the whole system and using PIM. So, I thought I needed that address. Well, as for traffic: Main / vlan 1 is my main VLAN with my smart home (Crestron) system in there, several touch panels for room control, which are also SIP phones on the same IP and such things. vlan10 is basically IoT with loads of Shelly WiFi devices and there needs to be a route to my control system on VLAN 1. IoT is getting close to 200 devices, so there might be some decent traffic and it should also have internet access for the sake of easy firmware updates. Vlan20 is Guest and at some point "guest" should only be allowed to get to the internet and have some ports for wireless video presenting on devices in VLAN 1, like AirPlay and such. The Office VLAN is my home office stuff for work that I wanted to keep seperated. vlan 40 is Dante for home audio distribution. in VLANS 30 and 40, there might be a bit of Multicast traffic going on (I work in AV and we are building AVoIP systems) so I wanted an IGMP querrier in the system and tried my best to get it through the whole network. Dante is anywhere and sometimes I had to put some AVoIP endpoints across different switches to test something. Then, VLAN 50 is intended for cameras, like home security, but as of today, the cams are still in VLAN 1. I got to move them at some point. This is just an explenation why the VLANs are the way they are....
I hate to remark this, but there are reasons for Rules #1 and #2:
The twelve Rules of Mikrotik Club
With all due respect 
, you don't sound like someone having the specific competence needed to belong to the very restricted number of people that can actually ignore them.
managed your Vlan properly 
you only need sfp+ DAC/AOC cable from CCR2004 going to the core switch and let the core switch distribute every vlan's to the other switches. you can achieve 10gb/s intervlan routing if you enabled the vlan filtering properly on the switches bridge.