In my opinion it is not too easy to gain TL3. At least in our community, which is not as crowded as maybe here (where it looks like the default values are not in use).
Anyway, I read through the trust level concept and also thought about the default values there. And I think, they make sense for communities like the one I am running Discourse for. But they do not match anymore when reactions are active. So admins would need to check the percentage of likes and reactions and adjust the numbers. And readjust after some time and checking again the percentage. Also readjustment is needed when adding more reactions and so on. And, at the moment, SQL queries are needed, which leads to Enhance About page website statistics again. 
So, I still cannot wait for having the reactions having their part in the trust level system and other parts of Discourse, where likes play a role. Optional for sure, but this is just a setting to turn on or leave it off and the traditional way. Also there should be some way to treat negative reactions, which I personally would keep as simple as possible (like flagging a reaction as negative and to choose if negative reactions are counted or not) - every community is a bit different.
Well, the trust level concept and also likes being a part of it was one of the main reasons for us to migrate to Discourse. So no, this would be the least I want. But as mentioned, every community is different and it is good to keep reactions out of it. 