How to space out interviews?

I'm interviewing with a unicorn (1000+ employees) now and had my last interview on Monday which I passed. I'm now at the virtual onsite, which is 5 interviews totalling 2 hours and 40 minutes across 5 interviews.

I scheduled it for Wednesday and Thursday next week. My question relates to the timing and spacing of these interviews. They don't seem to mind that there are 9 days from my last interview to the onsite. In the interim, I interviewed with another company today (and made it to the next round).

For the onsite, I have to present a project I worked on in detail with slides, so I will need time over the weekend and weeknights to do this.

My question is, can/should I ask for more time until I do my interview, pushing it Monday and Tuesday of the following week? This would put 2 weeks in between my last interview and the onsite. The pros of this are a) more time to prep for it; and b) more time to get offers from other places.

I guess what I'm getting at is what is a 'reasonable' amount of time to ask for? Am I pushing too much if I ask to move to the following week?

Thanks!