I'd go back to historical proportions myself.
Something to bear in mind is the "guns-per-thousand-men ratio" ["gp1km"], which I don't think was actually contemporary, but is a handy way to think about this.
What this was varied in practice according to locale, army size, and so on, but something like 2 to 4.5 would be about the usual bounds. So an army of 76,000 men with a guns-per-thousand-men ratio of say 3.25 would have 3.25 x 76 = 246 guns, i.e. Napoleon at Waterloo (at Borodino it was more).
If you work out how many men your force approximates to, you can estimate how many guns would be proportionate to that.
Your French Corps is, as I understand it, 3 brigades of 3 regiments, plus one Guard foot and horse regiment, plus four 2-squadron cavalry regiments.
If we take your foot regiments as having 2 battalions each of 600 men (wearyingly, all these values vary by era too) then you're representing 20 battalions = about 12,000 men. A French line cavalry squadron was let's say 150 men and you say you have eight of those, so that's 1,200 more men. Chuck in the Guard cavalry – usually these squadrons were stronger – and let's say you have 2,000 cavalry overall for a total of 14,000 men.
14,000 men are 14 thousands so 14 times 2.0 gp1km gives 28 guns, and 14 times 4.0 gp1km gives 56 guns.
You would therefore have somewhere between 28 and 56 guns for a historically proportionate artillery arm.
This is, of course, assuming your Corps-size formation is an autonomous one. If it were one Corps among three or four, its organic artillery strength would quite likely be less because there's an artillery reserve elsewhere which taken together with the Corps' artillery parcs would give you your overall guns-per-thousand-men ratio. It wouldn't often have any horse artillery either, as this would usually be with the various cavalry corps, though no doubt exceptions exist.
I don't know how many gun models per artillery unit your rules specify. But if it's say two pieces per battery, then your nine model guns give you four or perhaps 4.5 batteries, which is 32 guns or 36 guns, i.e. a correct and plausible ratio.
Where you are perhaps a bit heavy is on your 12-pounders which are 25% of the artillery you have. 10% of so was more common so I'd be tempted to make the Guard artillery unit an 8-pounder one.
Two guns in a French foot battery were howitzers, so you could justify having two howitzer models on the table if you like such things.
paints brigs for the British fleet.
