>>184637231. Use the Hydreigon for emergencies (or after the 8th badge when it obeys you. Unless you like it disobeying and falling asleep on you!)
2. Catch some other Pokemon and build a team (don't be afraid to use Pokemon from other games!). If you are still unsure of what to do, use the EXP Share. It's the "training wheels" for anyone who wants an easy playthrough.