Hi Snacks!
Many friends and I started doing MTB in 2020 because of that covid thing! I like this sport very much but I discovered like you that it requires a lot of knowledge to fully enjoy it!
1-Your fitness level is very important in your choice of bike. A friend of mine who was not particularly fit was recommended an All-Mountain bike which ended up with a weight of 35 pounds. As soon as he climbs, his hearts pumps up and eventually he often have to stop and retake his breath.... As opposed to me and my other friend in the triathlon team where we train all year long and we ride with extremely light cross country bikes which are often only 23 pounds, very good for climbing indeed!
2-But yeah descend is fun too so I agree that if you have to have only ONE bike, then a Trail bike is the best choice. That's why I ended up ordering a Carbonda FM1156 (now renamed FM1001) to have a more robust bike than my Santa Cruz Blur Trail. However the more you invest in more robust components, the more weight you add to your rig....
I knew I would never be a neck braker DH rider so a FOX 140mm fork and a Fox DPX2 is the best balance of performance without too much compromise in weight. Of course there are many similar possibilities...
3-You chose to build your bike like me and the others for two reasons: 1-MAYBE and I say maybe you are going to save some money by doing it yourself : but unless you are already fully equipped in term of specific bike tools, or you are going to borrow the tools ... then your first rig is going to cost you many hundreds of dollars in tools.
If you buy all the components for your bike you will see that they may be very expensive and in the end you won't save much compared to buy a brand new bike... But if you have spare or older parts from older bikes that you want to reuse, then you may save some interesting money! Where you save the most is by buying a Chinese carbon frame compared to a Brand name frame that can sometimes be more than 2-3K$ more expensive that a Chinese frame. 2-You want to experience the fun and satisfaction of building you own rig. By doing so you also acquire more mechanical knowledge making you less dependant on your local bike shop.
4-Rear suspension geometry: Horst-link (four-bar) and VPP are very popular, but I'm not sure it makes such a huge difference in light to moderate trail riding.
5-In the market of Chinese frames you probably know that there are very good brands as well as many bad companies. Go for Carbon and look for EPS molding, it appears to be better build quality and finish. For a Chinese Trail Frame I recommend you read the posts including mine with pictures of the FM1156/ FM1001. The geometry is quite modern and the build construction is very good. For now you can only have Medium size. For Large you'll have to wait until summer 2021. Ask
Adam@carbonda.com, pay with Paypal and always order their headset and a spare derailleur hanger! Good luck with your bike project!