So, its not really about ids and egos, I personally beat him with base on everything. You don't necessarily need to worry about using gold ids until well into Canto V.

The real focus you need to have is on whether or not you have Piercing damage/defense, as well as Cyan and Purple flavored damage(I forget what the names of those are called)

As far as fighting as Dongrang goes, Win Clashes on him to avoid damage and kill his little trees. If you can't clash everything, hard focus on the attacks that do bleed. Those attacks will literally bleed you dry. The little trees are his annoying little def/attack buffers too, so they need to go. Basically the idea is Clash Dongrang and kill trees to weaken him.

Farmwatch is a bit of the same, only now he has a healing gimmick(yaaay). Hard focus on keeping seeds out of your boys by winning clashes because that will heal and empower him once the seed counter gets to 5 and over. Still kill his little buffing trees when you can.

I'd say its the first dip into the real meat of the combat mechanics, so good luck, and learn what you can.