Hi !
I hope what I'm about to say will not hinder your will to learn modular, but I honestly think this video is a good example of a bad example :-) See, I don't understand the point of this rack, this looks like something one would throw together from modules you already have on hand just to say it's modular stuff rather than a build you would design as your only rack (no beef with Perfect Circuit though, they put out stuff I enjoy as well and are very nice people)...
In such a (very) small cab, I wouldn't even start thinking about integrating the TipTop One and Varigate just to trigger some samples. Since you're not going for a pure Eurorack setup, a small box like the Model Sample from Elektron or something similar will get you there for the same price and with way more functionality. A used Digitakt or an MPC One would be my first choice for sample duties if you can afford it. There also the software part to consider, IMO the Elektron world is slightly better than Akai's, but that's another discussion entirely, just think about it before buying and make sure to inform yourself extensively ;)
Keeping the drums out would allow for your Eurorack setup to be entirely dedicated to improving your existing synth setup. Crazy modulation and analog filtering/waveshaping is what I consider the main advantage Eurorack can offer to an existing synth setup like yours, so if this was for me, I'm not even sure I'd keep the 810 (maybe just get an 860 if you want that JOVE filter sound) and I would rather try to focus on using what the Eurorack format is particularly good at to expand/improve my existing synths. I would think about some nice filter designs the likes of which you only see in modular, say Make Noise QPAS, Xaoc Belgrad, Doespfer's Wasp, etc + fun/playable modulation like the Batumi you have there (I don't know it that much), the Acid Rain Maestro which looks dope, my beloved Noise Engineering Mimetic Digitalis, and of course attenuverters/matrmix mixers/VCAs to go with it. Maybe Marbles, a Turing Machine or an O&C, if space allows for it. I don't know about the MiniBrute that well but depending on its patch bay (the Hydrasynth's looks very limited) you could even think about fun logic and switching modules... But that's just me, what do you feel is missing from what you already have ? What attract you to the Eurorack format and what do you expect from it ? Are you absolutely set on this rack size ? What is your budget ? What is the type of music/sounds you are making ?
Trying to answer those questions might help you see things a bit more clearly, and sharing those thoughts on here will help others help you ;-)
Have a good one,
D.

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