I will say on the last one. But there are so many different strategies I have seen so far. You can score amazing results without even looking at your home board (except the last couple of rounds to cover ONLY the negatives) or concentrating only on your home board and build housed and/or emigrate. It all depends on your strategy - which actually will (should) be different in every game.
That would depend a lot on how many of the bonus spaces you intend to take advantage of.
does that really matter that much ?
It does matter quite a bit because if you are willing to ignore the bonus goods, it becomes much easier to fill in the board by putting tiles down and not trying to work around those bonus good spots. However if you are asking how to best make use of the home board strategy, then you probably do want to take advantage of these bonus goods along with income.
I'm not sure if you're asking for solo games or for multiplayer games as there is a difference in what you can reasonably expect to achieve.
With all that being said, I can at least try to give you some idea of what you can shoot for, but there is no hard set rules for this stuff, as many of the people here were trying to make clear. There are so many strategic paths to take in this game and no set strategy one can simply employ.
As is, here is roughly what I would aim to do with a heavy homeboard strategy:
Round 1: Reach 2 income. This is pretty easy and is pretty much the opening move for anyone.
Round 2: Reach 4 income. Unlock the Mead bonus good. Possibly unlock the wood, ore, or stone in addition.
Round 3: Reach 7 income. Have unlocked all 5 bonuses from the homeboard.
Rounds 4-5: From here you have quite a few options. In general I think you will stand to get the highest scores by grabbing an exploration board or something else. Reaching higher income will take quite a lot of effort for fairly minimal gains, and you'll earn more total from getting an exploration board and filling that for more income and bonuses.
Round 6: Get your homeboard up to 12 income. This leaves a 2 wide boarder for the last round which generally is a good idea. If you push to a 15 income it can be very hard to find 1 wide pieces to fit in during the final round.
Round 7: Fill in your homeboard for 18 income.
Again, this is simply a rough outline of what you could do. There are so many paths you can take and try in this game and by no means if this even necessarily an optimal path to take.