<rant>
I try and check the release notes every time there's a new Domo version to see what's new and improved. I was very excited this morning to see that spark lines and spark bars have been added. Yes! Unfortunately, they're a total disappointment. I'll try and stay polite, but I just can see any reason for these new chart types, as they exist.
For review, a spark line or spark bar is a small, unadorned chart that is embedded in a larger presentation. The idea is to show a trend visually without distractions. but in a context that supplies the missing details (scales, values, axis labels, etc.) The benefit of a spark line is that it highlights one thing in a larger context. Without the context, all you've got is a chart without enough information. Domo is getting it backwards. The benefit isn't that you're removing information from the chart, the benefit is that you're removing redundant detail from a dense information presentation. Without that larger context, all you've got is a bad chart. The little call-outs are nice, but also highlight the problem: The chart alone means nothing without mousing around over it.
In practice, I don't think you should call these new chart types spark lines/bars. They're just less adorned variants of your existing bar and line graphs. Please add real sparks lines and bars Domo normally does an excellent job of making it impossible to create garbage charts. For example, you don't allow plotting imaginary 3rd dimensions, don't go in for pointless chart adornments, and the like.
Domo is quite powerful and is a great tool for painlessly producing attractive, accurate graphs of a wide variety. But as a graphing platform, the most fundamental missing feature is the ability to create comparative charts. You can assemble multiple charts on a page, but that's not the same as a table with sparks. Nor is it the same as real multiple miniatures. To make Domo a complete graphing platform, it needs to support linked comparative charts in a single presentation. Put another way, side-by-side charts on a card. And chart + data table in one view on a card. (Pie chart does this but, honestly, take out the pie and how much information do you lose? None.)
</rant>
Below are links to a few existing suggestions for comparative chart types or modes:
Sparkline Support
Small multiples for appropriate chart types
Slope chart (slopegraph) support
P.S. Is the limitation that you're using Canvas instead of SVG under the hood? Linked multiples are pretty natural with SVG and, obviously, a whole lot of rendering from scratch with Canvas.