Any suggestions on which packs to buy for someone new to the game?

(continue from previous)
If you invest time into the game, events, leveling up characters and farming, one day you will see you hit the 9999 gems upper cap. Then you talk about building top tier deck. And also by that point, you will have more knowledge and what box to buy already..

I have slightly different opinion than others. You said "only 2000+ gems" and "you are someone new to game". In that context, you should build a farm deck first. Then slowly you can level up characters, farm LD, farm events for rewards/ SR UR stones/ skills drops. Sorry but if you want to be strong in PVP, 2000+ getms aint gonna cut it. Either you can (1) dump lots of cash into P2W player (2) build a farm deck and improve your decks slowly.

Dawn of Destiny for Naturia Deck or Phoenix
beginner deck.

There are a several options you should consider.

Investing in packs with cards that can work in many decks in general or investing first in a pack for a specific deck.

Mirror wall from neo impact is a strong card that can work in almost any deck.

Wall of disruption from Servant of kings is a slightly different mirror wall, but from a mini box.

Ultimate rising pack if you want sphere Kuriboh.

Dawn of destiny is a mini box with some strong cards.
Naturia deck that you can build with it has been quite an allround deck for a while now.

Its up to you what you want to make but the ones i mentioned is what i should take a look in first to take into consideration for your decision.

Enemy controller and Windstorm of etaqua are not from packs but are farmable cards that i can really recommend if you werent trying to get those already.

Enemy controller is from either ranked sr ticket or beating kaiba at the gate (recommened to farm the lvl 40 one and if too hard the lvl 30 one. There exist guides for it).

Windstorm of etaqua is from lvling up Mai.

Hope this helps.

My suggestion would be to roll a pack, that let's you build a proper PVP Deck just by itself.
For example:
- Electric Overoad for Ice Barrier Deck or Ninja
- Dawn of Destiny for Naturia Deck or Nephthys

Just look through all the decks and make up your mind on which kind of deck you wanna build :)