Hey...
Well,welcome to the hood...
It's a good thing you're motivated and it's best you keep that up...

q1.
The reason training to remember your dreams is so that:
1. You won't forget a Lucid Dream...
2. To find some recurring DreamSigns...

q2.
There are plenty of things you can do to increase the amount of Lucid Dreams you have...such as:
1.Reality Checks
2.Auto suggestions (mantras)
3.Motivation,spirit,belief and confidence...
4.As well as sticking to a technique such as MILD or DILD...

q3.
Well it's perfectly natural for a Lucid Dream to come out of the blue...Also,there are many people who you may call "naturals"...I myself had 2 Lucid Dreams when I was around 7-9 years old and had no idea what Lucid Dreams were...hell!I didn't even know it was possible to control dreams...

Well I hope this helps,
Keep practicing and before you know it,your first Lucid Dream will come...
Cheers,
Sam