So like appearance rate

Ok, I did the calculations using the CYL1 rerun that's on right now. I have updated my counts of the 3*, 4*, and 5* pools. One thing I noticed is that the CYL2 units are not yet in the general summoning pool; they are not yet capable of pitybreaking you. Once they are, the chances of finding Soleil worsen, but only by a hair. It's mainly demotions (Sylvia is being talked about as a possible demotion) that would make harder to get her because if you get her, chances are around 95% that she's 4*.

And the numbers will vary a little bit depending on whether there is a red focus unit / how many red focus units compared to focus units of other colours, but they won't change drastically. On CYL1, 1/4 focus units is red, and focus rate starts at 3%. Soleil will appear as a 4* from approximately 1 in 52 red stones and as a 5* from approximately 1 in 774 red stones. Collectively, that makes 1 in 49 red stones (if you find that 1/52 + 1/774 does not equal 1/49, it's that these are all rounded numbers). If you pull only reds on this banner, you could reasonably expect to see her once in 250ish orbs.

For comparison, I checked what it's like if you want Sothe instead. (He's also 4*-5* only.) 4* Sothe is 1 in 47 colourless stones; 5* Sothe is 1 in 700 colourless stones, and they add to 1 in 44 stones. If you pull colourless only, you would see him an average of once in 240 orbs.

I also ran calculations for someone like Marth who's also red but who is 3*-4* available. Much better. They're both in the 4* pool with equal probability of appearing, but 3* Marth is around 1 in 79 red stones, which is about ten times better than 5* Soleil's 1 in 774. Marth of any rarity would appear from about 1 in 32 red stones, which is about 165 orbs.

Now here's the part that's maybe sad, or maybe not. On this CYL1 rerun, B.Roy will appear from approximately 1 in 39 red stones. You're more likely to pull the focus red than you are to find any Soleil, pitybreaker or not.