Does the amount of email I send from my IP affect my deliverability?

Yes. Generally speaking, you don’t want too few IPs, in case you experience more volume than you expect and you don’t want so many IPs that you look suspicious or spread out your volume over too many IPs. There has to be a balance of volume to IP/domain. Sending too much volume from an IP, sending from too many IPs or sending too little from a range of IPs can all lead to deliverability issues