DPIV user (A500/512+512k) as a kid/teen in the 90s, been testing things out in pixels again recently.

For a more modern substitute with layer support, GrafX2 is often mentioned. It's a pretty damn good indexed color pixel tool, sort of a child of DP and Brilliance. Still has the brush and foreground/background color essentials and other things.

- By default, it shares a lot of keyboard shortcuts with DP, with a few key ones being replaced by more modern conventions (you can change them all, apparently).

- It'll open HAM and half-brite images, but will just essentially consider all of the colors as independent (ie instead of automatically deriving the last 32 from the first in H-B), so beware when doing some back and forth.

- It has layers / can handle animations as a result. If you save an image as a gif, all layers become independent frames when the gif is opened somewhere else. Conversely, give it an LBM animation, and it'll load it in the layers, and you can play it back.

- You can start it with a commandline argument to limit its bit depth, so `/rgb 16` will get you to the Amiga's 4096 colors. Apparently dpaint.js can reduce to Amiga colors, but I haven't found where it is and have had colors display wrong in Amigaland in my tests (one doesn't simply reduce to a few colors!). I might have to ask the author about that.

Back then I filled most of my floppies with Star Wars spaceship animations made by combining the perspective and animation tools (as explained in the very thorough manual) - until I ran out of memory and couldn't finish a lot of shapes. People have posted legacy VHS video tutorials, basic and advanced, for both DP3 and DP4, up on YouTube. A lot of what's in there is in the OG manuals, but it's quite a different perspective seeing it in motion, explained by a real person.

- DP3 video guide with insights from Dan Silva - https://www.youtube.com/watch?v=4qTv8qnTzYU

- DP4 basic video guide - https://www.youtube.com/watch?v=973fiFaSXqw

- DP4 advanced video guide - https://www.youtube.com/watch?v=KybIkyilCQI

Anyway - In DP4 at least, an animation would be saved into a single file, which I found out in some recent exploration gets tricky if you never stuck to a naming convention as a kid :) DP4 doesn't care about the extensions and will happily load an animation as a still image (and just show you the first frame), although it might complain in some other directions (image as anim, brush as image...). Thankfully, GrafX2 can tell the difference! You open the file regardless of it being a picture, brush or animation and it does the rest.

As for doing stuff in emulation, for sure turn up the emulated hardware specs, good call from the author there. Don't even really have to step away from cycle-exact, just going up to a 030+FPU or 040 is already a big relief. Mounting part of the real filesystem is great too ; and since you're emulating a faster machine, I'd just upgrade from 1.3 to 3.1 too for a bit more creature comforts (3.1 is rough enough as it is, but it at least allows you to list files without icons in the GUI...). On that front, I would also suggest maybe using noicons in DP - spamming the host filesystem with .info files (icons - also IFF/ILBM and viewable in Grafx2!) gets old fast IMHO.

Used my Wacom tablet a bit as a dumb pencil mouse through the emulator, and even without pressure sensitivity, it was already so much better ; although the "right click to paint in background color" thing is really awkward there. I had to make sure windows pen input was disabled, and that was it. It's possible to get pen pressure in the amiga with DP5 but... that's quite the can of worms, and I wouldn't even try this on emulation.

As for alternatives on Amiga, I also tried PersonalPaint (got the actual licence in my AmigaForever package some years ago), but besides color reduction, error-diffusion dithering and other effects, I couldn't jive with it. Newtek Digipaint was interesting to play with ; you always work in HAM there and have interesting brush expression parameters. It really makes it obvious that you have to plan your piece and pick your base 16 "real" colors before you start doing anything. Haven't found a copy of (True)Brilliance to play with.