some observations:
your voice sounds fine. i'm a native english speaker, and i understood things fine. you have a very good storytelling sound to your voice. i didn't understand some of the jargon phrases like "Venture forth to hunt". i literally have never heard words put together like that, so it caught me by surprise. but normal words like "54 percent" were easily understood, because i am used to hearing them. so as a quick improvement, study your pronunciation on the technical video game words like "light cone ability". maybe put them into google translate and see how your vowel sounds differ from the computer (you can use google translate as a prounciation tool by typing the words into the text box and then hitting the speaker icon). a wrong vowel sound can completely confuse a native english speaker, especially if it is a word or phrase they are unfamiliar with or are not expecting. don't worry about how you pronounce obvious words like "before" "after", "blue" etc. we'll be able to figure the easy words out. just practice the jargon words.
the vocal is over-compressed. there is very little competition from the background sounds, so there is no need to go to nuclear-level compression. even great voices, great mics, and great processing equipment will sound terrible if you over compress. so back off the compression. you don't need hypercompressed vocals with instructional videos. you need
clarity, with a mild amount of dynamics management.
the compressor you are using sounds low-grade. are you using a stock compressor that is included with the audition software? if so, there is probably room for improvement. audition can use VST effects, and there is a world of high quality third-party VST compressors. an excellent one is the SSL Bus Compressor. It is expensive, but sometimes SSL runs a great sale where it is only maybe $40 instead of $320. the end of year is when a lot of audio software plugins go on sale. so look for a sale. another good compressor with an everyday low price is the Waves Renaissance Compressor. you can usually get that for under $40. Waves has a bit of a clumsy digital rights management system called Waves Central. It's not terrible, but the SSL bus compressor has less hassle. There are SSL bus compressor clones, but the real one written by SSL itself is the one you want. Even though it is called "bus" compressor, you can use it on a mono channel like voice. I use it all the time. it is excellent.
your converters sound a little cheap. what is your interface? some people think converters don't matter- they are wrong. preamps and converters make a substantial difference. if you are at the budget tier interface level, spending a few hundred dollars will get you better preamps and better converters.
your mic sounds a bit hyper, and is contributing to a lot of sibilance. what mic are you using? the high frequencies is one area where quality mics separate themselves from the cheap stuff. the high frequencies sound cheap.
you are putting a lot of work into your videos. i think you deserve high quality audio equipment.
my recommendations:
get rid of the compressor plugin you are using. get the SSL bus compressor written by SSL itself when it goes on sale. use it moderately. don't crush the signal.
get a better interface. an apogee duet 3 will get you into professional grade preamps and converters.
get a better condenser mic. cheap condenser mics have cheap high frequencies. in order of price/quality: Audio Technica AT 4040, Neumann TLM-103, Neumann U87ai
you get your best improvements per dollar spent on your transducers (microphones, monitors, headphones). so if you had to buy one thing right now, it would be a better condenser microphone. you can get a free compressor of good quality such as the TDR Nova- it's labeled as a "dynamic equalizer" but it does all sorts of range control functions, including standard compression:
https://www.tokyodawn.net/tdr-nova/
when the SSL bus compressor goes on sale for about $40, buy it. then later on, you can upgrade your interface. so you can improve your signal chain in stages. start with the mic.
you are in germany. you might be able to get very good price on neumann mics from thomann in germany, since neumann is a german company. the neumann u87ai is the world standard for voiceover mics. it excels in clarity and professionalism. the neumann tlm-103 is a low cost, high quality alternative to the u87ai. it is also used by voiceover professionals worldwide, and has one of the best signal-to-noise performances of any mic in the world.
so if you want to a get better mic quickly and affordably, the AT-4040 will get you there. if you want to jump straight to where a preponderance of voiceover/narration professionals are, look into the u87ai and the tlm-103.
rme is a german company that builds very good interfaces. so if you wanted to build a professional all-german electronics collection, you could get an rme babyface and pair that with a neuman tlm-103 or neumann 87ai. add in the ssl bus compressor plugin, and you have a 100% professional-grade setup.