First another comment on choosing a canvas: I found another example of what used to be a great beginner piece - and still would be when properly drawn and painted. That is, it needs to be symmetric and stitch painted!
This one is cute, but the little dots are lopsided, as is the bug itself - and the antennae are crooked and would be confusing to stitch for a beginner. A pattern this small would not be attractive stitched as it is.
About having that much background - I wouldn't put that much on a beginner piece and expect anyone to do it in basketweave. This is where a bit of texture might be introduced. A simple stitch such as T-stitch (the way I do it that covers the canvas) because it's not overwhelming, and because it would make the background work up faster. A diagonal stitch would be awful in this case!! So would mosaic stitch, as it's square, and would not be attractive butted up against the round contours of the bug.
I used to teach on a ladybug, myself, long ago, as it has the elements I needed to show how to stitch on a curve, and also the antennae going in two different directions. This is a thing that is difficult for people to get used to - making ALL of the tent stitches going in the same direction, as the tendency is to want to point them in the opposite direction here. As I've said before, the sawtooth effect is just a characteristic of needlepoint.
This is also a good design for demonstrating how to find where to start the basketweave, as it's different from just starting in the upper right corner (lower left for left handers). As for where to start, this picture is from my tutorial on stitching background around irregular shapes, so you can see the rest of it on Freebies, etc. (I think that's where it is).
Anyway, a piece of paper may be placed on the EXACT diagonal of the canvas, and moved toward the curve - you can see clearly where the first stitches will be. I still have to do this on some of my elaborate designs, such as the leaves on the Celadon I'm stitching right now. It can be confusing!
The leopard spots also show the advantage of stitching them first before background, as a lot of shaping trial and error is going on here, even though I painted them carefully. They are not solid only because I left the gaps to insert beads - this was intended for the top of a hat Vikki wanted to make.
Although it wasn't the subject of the tutorial, this series also shows, as in this picture, the advantage of stitching DESIGN before background. If one does background first, there is danger of misshaping a part of the curves.
I learned this the hard way long ago. I was doing a little cherry on a keyring for a friend, as it was her name - I worked the background first, but when I stitched the cherry, it looked like it had a wart on the side. It looked fine until the background was stitched around it.
The next photo is a detail of the Celadon piece I'm working on for my son - on the lower corner I noticed the date on it is 1996. Oh dear. No wonder he keeps asking me about it. He bought me the bowl from which I adapted it. The arrows are simply pointing to elements of the pattern than needed to be shaped before background was stitched around them.
In looking at the corresponding squiggle on the left side, I can see where I should have added one more brown stitch, as it appears to have a lump on it, but eliminating these few stitches in the shaping would have made it too flat on that side. Too late now, and the work is 15" diameter, so maybe nobody will notice if I don't point it out.
This is for framing for his office, and I don't think a bunch of lawyers will be too concerned with it. I did stitch in the coin in Kreinik metallic braid (002V) BEFORE outlining it, because the braid might otherwise have pulled at the DMC floss stitches of the outline if I had done that first. In this case it was O.K., as the coin is stitch painted.
In doing all that outlining first, I was able to shape the elements more easily - as the leaf the arrow shows. I like a good balance in stitching between outlining and background (or pattern vs background). Background can get boring - so working something a bit more challenging and then taking a break with working background around it is good.
The last photo is a canvas I designed in the mid 80's, and had begun to stitch, but had to put it down for other things. At that time, there still were no novelty threads, and using textured stitches was rare.
On looking at it again, I want to re-paint it, but smaller, on 18 mesh canvas, and use just a little bit of texture. Too much would ruin it, but that background is rather daunting to think of doing in basketweave. I'm thinking maybe just simple T-stitch, and needle blending at the bottom where it shades to blue and purple.
The veins of the sea fan show the "design before background" principle. However, at this point, instead of plain old basketweave, I think the fan could stand some subtle sparkle and a tiny bit of texture - I'll have to think about that.
This canvas really has possibilities for using different thread effects and a few decorative stitches here and there. Hmmmm. I'll get right on it as soon as I have time.
Hopefully you can see at this point that stitching the painted canvas needn't be frightening - one learns gradually, after mastering the basic basketweave, to introduce a few well placed and carefully thought out decorative stitches. You can look through books and try out a few that look interesting, but there is simply NO need to master dozens of them, just to be able to use long, fancy names and show skills that aren't necessary and make the work tedious rather than relaxing and enjoyable - it just isn't required, and it makes a goopy mess if overdone.