Have a look at the washing nappies board for some tips on how to do a strip wash. It might help although, in my experience, night nappies tend to honk of amonia no matter how you wash them - I guess because of how long they're worn for and how much pee there is in them. I just whip them off and get them in the nappy bucket as quickly as possible and try not to breathe while doing it!
The Ella's house aren't a bad buy. We always had to boost ours but, like I mentioned, my DD is a very heavy wetter. We certainly couldn't use them now.
Boosting can be done either inside the nappy or outside it - doesn't matter which, just make sure thath the fit of the nappy itself isn't compromised by boosting. And make sure that your quicker absorbing fabric is the top layer of any boosting you use (so bamboo on top of hemp or MF on top of bamboo, whichever you prefer to use).
As for good night nappies, it depends what you're after. A WAHM (work at home mum) nappy will always cost more than something you can get at a nappy retailer. Non-WAHM night nappies that you might consider could be Baby Behinds or Swaddlebees OS (we used both of these from when Iris was about 12 weeks old and I always had to boost them). WAHM nappies do tend to cost more, but do tend to preform better. And there are hundreds! We have used:
Holden's Landing Bedbugs (from the US though)
Upsy Daisy (no longer made, although Amber - who made them - now works with Beth of Luscious Little Somethings and those nappies are meant to be good, too)
Those are all fitteds. I know some people prefer a pocket and have used standard Minkis (by Nappies by Minki) with great success as the pocket for stuffing is huge.
Just had another thought. Rather than using huge amounts of boosting, you could always just use two day nappies at night. Sounds mental, but it works