Krayl

The easist language you can start with ( in my opinion ) is Visual Basic.

Kali Linux has many preinstalled applications, It's really nice for ethical hacking and you can practise alot on it.

Can you tell something about the range ?

If the router has 802.11w Protected Management Frames they can't be deauthenticated.

But for the mdk3 exploit you could just use aes only to avoid that, and for deauth there is 802.11w at the moment. In a few years there need to be new exploits

Maybe no more TKIP exploit, like Michael shutdown exploit (mdk3) or no more deauthentication attacks.