
Sorry... both in the graphic attached, and in all the text, when I say "arrow" the word is really meant to be "triangle" (as seen in the graphic, which is really not an "arrow").
1) Yes, via preferences. It is only needed there, and I (and probably other artists using Photoline) would not mind at all if by default in installation it is set as other cursor type if other users prefer it so. As I have seen that the software remembers the settings between sessions. The digital painters would change it as needed in preferences, as we are used to do.
2) Sorry, I was not precise with my explanation. I have made a graphic mock-up (I inserted it below), indeed, capturing exactly the cursor icons from certain painting application, cursors which are the least obtrusive/distracting of all the painting apps that I have used, and these give the possibility of working in all situations in painting. It would be ideal if both could be added.

With the triangle, of course, the active point (which paints the pixels) is supposed to be on the upper tip of the triangle.
I don't know if the borders of each icon are exactly so, as I captured it with the print-screen key. So, I don't know if there's some openGL blur or something, in that app, and if so, I don't know if those are the 'exact' pixels. But I guess something very similar would work perfectly. This has been refined through years by painters requests, so, they seem to work well for painting.

Basically, one is a thin black solid triangle pointing up-left (maybe in a -45º angle, I'm not sure). The other, seems to be very few black pixels forming a circle. I have tested often cursors made of one single pixel, but that is not seen in higher resolution screens and is bad for people with poor eyesight. One of the reasons why is good to provide both cursors. The black "dot" formed by very few pixels allows for work without losing focus (it is my favorite), and very precise lines, too. The other, for people liking to see bigger cursors, yet having precision and neither being too distracting. It is also good for any user in certain situations (I use both, although mostly the tiny black circle one).