As Jim mentions - its a pretty small space for a full on system, and it will certainly lack quite a bit of control of which makes modular worth the plunge to begin with.
Another good starter case might be the ALM DIY cases, as they start at 3u 84hp, and 6u 84hp - this is a little more room to get a few more necessities into the case to make your first full case patches worthwhile/exciting to come back and learn with. Decent price if you are okay with the small amount of building it requires.
My first case was 84hp and had a similar module compliment (Make Noise Telharmonic oscillator + Maths + MMG + Optomix) - within the first month or so I had another 7u performance case on order, as well as another 84hp of Roland system 500. A small amount of modules can certainly breed creativity, but it can also be a real nuisance when you can't achieve the sound in your head simply cause you lack needed utilities you don't have room for. I would constantly patch simple ambient drones that sounded cool, but ultimately a lot of money for the result. This is something you will learn over the course of messing with your first modules - you currently have the idea of creating a relatively complex synth voice, but the choice of modules will inevitable end up not providing much in that small case/setup without significant external control / constant hands on modulations. You may find after some initial experimentation that you want a completely different system, which is fine, but hard to achieve if you stick within a certain size constraint, and something you will never know without taking the initial plunge to start. There are always newer/smaller/more feature packed modules at any time that do what you want but better.
As for starter modules as an option - I would suggest the Dreadbox Chroma series, as bang for the buck they have a lot of good functionality and features for small systems.
The Intellijel Palette style cases are pretty shallow (I own both the 62hp and 104hp) - so I find keeping a pack of m3 standoffs can be helpful to raise the module up a bit to remove pressure on the power connector (won't sit flush with the other modules however).
Switches/VCAs/attenuators & attenuverters are your best friend for modular, as they allow you to patch/setup a modulation depth - and then turn it on/off as needed at any given moment (some are CV controlled to which is great - Acidlab Switchblad or ADDAC VC Rotator for example).
In the end - modular sequencing/utilities is really where eurorack starts to shine in my opinion - all my smaller cases have been relegated to control or mixing skiffs for larger systems I own.