I've played this game twice now, straight through to 100 getting the Genie.
Its actually quite easy - and I don't mean that to sound facitiuos.
DON'T use your bonus' willy nilly. Save them so that as soon as you get to a level that you can't beat, you have most if not all of your bonus' to the max. You may find that you only have to use 2-3 of them to get though a difficult level.
Once you make it though, start building them up again - even though you may not get through a level the first time and loose a life.
What I found both times is that by the time the city is built I have 20-25 lives which is plenty to do a level with the only intent being to build what ever bonus you have - then again, once you have all of the bonus' built up again, use as many of them as you need to get through to the next