The base (max of 99%) and the total are the ones you should focus on the most, the rest are to explain how you got from the base to the total. Adjusting the values of those is pretty easy Level gap can be fixed by getting each pokemon to the same level low level is fixed by leveling the pokemon up happiness, put them in a field that makes them happy/feed them happiness items as you can see with my alolan persian pair, you can indeed maximise how effectively they breed by knowing what to look for and how to adjust

Ok, so every other percentage can change now just not the base? Like before?

Yes, the only part that has changed is things are now shown to you, rather than ambigously being unsure of what you may be doing right or wrong with your breeding

Oh ok, thanks for the info :)

I'm really confused on how WT fits in. If there was no regular trading before WT, is the OT the last person who WT'd the pokemon?

wonder trading works exactly like normal trading, the first person who traded it is locked as the OT

Can I use a Shelter pokémon that I'm not the OT to make a pair or not it will not work?

This only works if the pokemon has been traded before being put into the Shelter as it would have had the OT locked in as the first person who traded it. OT isn't the breeder/hatcher, it's the first person to trade it away. So if you adopt a pokemon and try to pair it you will be seen as the owner and it wont give you a 99% unless it is traded.

Thanks. I was thinking about it. :D

Give the guide a read-through :) PRETTY MUCH any question you could have is answered with details to explain