expireddomains.net flipping domains methodology

Hello good morning, I want to be as detailed as possible on how I am generating some money by buying and reselling domains using the expireddomains.net website
It is a very simple methodology and I think you can help me improve it.

To buy domains that I consider to have value and then resell them on the Namecheap market: $5 to $19 usd
Sedo: $5 to $19 usd
Afternic: Value over $50 usd

70% of the domains are sold on Namecheap, Sedo 20% and Afternic 10%.

I think this is because under the modality I am working with trying to hunt for opportunities on expireddomains.net, most of the domains have a value between $5 to $19 usd.

I'm very comfortable registering domains on Namecheap since I sell 70% of them there, so adding them to their marketplace is a matter of 2 or 3 simple steps.

I think I can do better and here is my step-by-step guide that I consider when registering and what things I'm overlooking but that I know are relevant and that I've been learning here on this forum:

Currently I look at words with a high search volume on Google, words that exist in the dictionary and relevant topics. It's gone well for me, but I want to improve the process.
And i look number of TDLS registered with this domain.
These 2 things are what he told me the most about, nothing more.

So, what other things should I look for to make a domain valuable? For example, I don't take into account information that the platform shows such as: TTF (Majestic topical trust flow) or the trust flow, the trust ratio, the citation flow, I don't analyze the backlinks or anything like that.

My question is whether a non-expert buyer will look at backlinks when buying on Namecheap, or rather; Those who know about this, like most of you, are looking for opportunities on Namecheap?

I also have the same doubt for Sedo and Afternic; do I have the opportunity to increase those percentages mentioned above if I look at other information such as:

Backlinks, TTF (Majestic topical trust flow), trust flow, trust ratio, citation flow, I'm not looking at any of that.

I'll be waiting, greetings and thanks.