Most of my bottle conditioned brews took 7 weeks - 4 weeks in the fermenter (usually primary only) and 3 weeks in the bottle. 4 weeks total is a little short if you ask me, but 6 weeks is a good timeframe. The schedule you propose should work fine, in my opinion.
It should indeed stay rather cloudy since it is a hefe. That's the style.
And, yes, the hydrometer is the only true confirmation as to when it is safe to bottle. Fermentation can get stuck and, no matter how long you let it sit, it won't start again until you transfer it, give it more sugar, agitate the yeast, whatever. Bottling beer in that state can easily result in bottle bombs.