Everyone has a different approach and there's no 'right' way, however, I would say gaps between drafts are vital to give you the objectivity to analyse the text properly in the next draft.
I also think it's a good idea to (as
@Tim James has suggested) write something else in between drafts to give you more distance from the last draft.
I'd also suggest that you plan more at the outset, but I know some people have to 'pants' their way through.
In my current novel I've found it very useful to separate the plot points from the narrative points. What I mean by this is that the plot is often a series of cascading cause and effect where one character learns particular piece of information which causes them to act, which causes another event, then another event and so on. The narrative is how this information is learned and what the character does in response.
E.g. A plot point may be that your protagonist learns that his wife is having an affair. Whereas the narrative may be that he sees a text from his wife's lover on her phone whilst she's in the shower. Ultimately, this narrative is not particularly exciting, so on a redraft you might decide that instead he walks in on them in bed together as this still satisfies the original plot point but achieves it in more intriguing way.
This makes your novel more fluid and it makes it easier to conceive developmental edits when you're not tied to a fixed series of events.
In my first novel I really struggled with this and rewrote my chapters to death, but changed very little of 'what happens' as I developed a very fixed idea of what the story was about and failed to see that my plot was a series of random leaps forward that didn't make complete sense.
Whereas, partway through my current WIP I realised that I didn't need to introduce a new POV in the second part (as I'd originally planned) as a minor character that had appeared a few times in the first half, could satisfy all the plot points that my new character was going to have to get through in the second part. Using a character that the reader is familiar with is easier than trying to introduce a whole new character to carry the plot forward.
I've also found that after I've done any developmental edits and once I'm on to cutting the text down that printing the text off (I'm sorry trees!) and reading the text on paper is easier to spot filler words and excess sentences, which I can cross out on the paper version then change on the digital one.