I like your question though I don't really have a set answer for it. lol
I belong to an apologetic site so I tend to spend many hours studying scripture.I do usually spend any where between 30 minutes to a couple of hours alone reading my bible everyday aside from the apologetic studies.
It is actually kind of hard to put a time on everything as I spend all day with God.It is a relationship.When you are in a relationship you don't just talk to the person for 30 minutes and then not talk to them any more for the rest of the day.
I spend time alone in prayer every day but I still talk to God throughout the day.I sing songs to Him,praise Him and thank Him.I may remember something else I want to pray about while I'm washing dishes and then pray about it.So it is an all day,ongoing relationship without a time limit.
We are to abide in Him!
John 15:5 I am the vine, ye are the branches: He that abideth in me, and I in him, the same bringeth forth much fruit: for without me ye can do nothing.
6 If a man abide not in me, he is cast forth as a branch, and is withered; and men gather them, and cast them into the fire, and they are burned.
7 If ye abide in me, and my words abide in you, ye shall ask what ye will, and it shall be done unto you.
8 Herein is my Father glorified, that ye bear much fruit; so shall ye be my disciples.