Actually I don't see Goku as being a TERRIBLE father, but he WAS an immature one....
Remember, Goku sacrificed his life not once, but TWICE in defense of his Son Gohan...
When the world was at stake and Cell was bossin around like he was invincible, Goku, as a father, put all of his trust in Gohan. That's a hell of a legacy to pass down to your pre-teen son and have the CONFIDENCE that he could get it done. Remember, Goku was seen throughout the UNIVERSE as the premier warrior. Having defeated the destroyer of planets himself Frieza, being the first Super Saiyan in thousands of years, he set aside all pride and ego and told his son that he was in fact, stronger than him
Goku had trust again, in Goten and Trunks, that they could learn the fusion technique and defeat Majin Buu, again, seeing the potential in his Son and encouraging him against seemingly impossible odds.
The one smart thing that Goku did in all of this, is forsee that ONE DAY the world's heroes would have to survive without him. He did what he could as far as making sure his two sons had the proper training to defend the world in his absence, as a father I commend him for that...
Now going away to train Uub for 7 years is just ridiculous.....
But again, you have to look at how Goku himself grew up. He was an alien kid with NO family whose adopted grandfather died when he was young and left him in the middle of a forest with nothing but a hut and a Dragonball. Goku didn't grow up understanding proper family etiquette and dynamics. He was mentored to fight and from a young age was forced into heroics. Hell Goku didn't even know what the hell a "wife" was, he thought he and Chi Chi were going to have some kind of special food....