How many blessings/boons can you normally have each attempt?

[Vin]

20 minutes is not that long and you'll probably finish the attempt around level 40-50 if you maxed out your exp gain, but I'm curious and can't seem to find the definitive answers anywhere. From what I noticed without the help from Alteration Ritual Blessing, you can only have 1 weapon blessing, 1 dash blessing, 1 trail blessing, and certain ability blessing is also limited, for example you can only have Meteor Shower or Lightning Bolt, also It seems that you can take up to 8 Autocasts Blessings (Merris achievement), but I'm not sure if this is the Autocast limits.
So what else is limited? Is Buff also limited? The most Blessing that I remember having is 22 Blessings, but with Alteration Ritual Blessing, I can have around 25. So is this it, or can you go even further beyond?