This response got a lot longer than I thought it would be.
In my experience, there's a sort of decimation effect that goes on between levels of engagement. Since my tumblr blogs have the best and most long-running data, I'll use those as an example. My largest blog has just passed 9,000 followers. That sounds pretty impressive, though you have to mitigate that by the fact that it's 6 years old and large numbers of the first 1-2 thousand are probably dead accounts that nobody is reading with. My posts tend to get 150-300 notes most of the time. Think about that for a second. Likes and reblogs are the easiest thing in the world to do, but only about 3% of readers do it. I can't know how many people are actively reading, but a lot of them are non-interacting lurkers.
Some other stats, I recently started a secondary blog with another comic on it, and that quickly shot up to about 900 followers. Some of this traffic is probably from other sources, but let's put that to one side for now. That's a 10% conversion rate. 10% of my followers are reading and paying attention and actively engaged enough to follow me to a new comic, and also happen to be interested in that comic. I also have a Patreon page, which currently has 64 patrons, closest to the most it's ever had. This is about 20% of the note-giving readership, and 7% of the follow-me-to-another-blog readership. You can mitigate this for the fact that not everyone is going to have disposable income to spend on things like Patreon, but it's still going to be in the range of 1% of the total follower count.
You see the general pattern here. About 10% of my total followers are active enough to follow me to other places, and about 10% of those are engaged enough to offer financial support. (They're not all the same people, but that's the way the numbers add up). It should also be noted that the proportion of those people giving a very large amount is also around 10%.
It should be noted that not all engagement is created equal. I have YouTube channel as well, that has about 18.5k subscribers. What I post there is usually animation, which has a bit of a weird pattern when it comes to converting subscribers to views, so that's not particularly useful. But it links to the same Patreon page, which means that around 5% of YouTube subscribers convert to Patreon patrons. A YouTube subscriber is just not as engaged as a Tumblr follower.
When I'm looking at the numbers you've given me, you're not actually that far off the ratios. If I take "a few hundred consistent readers" to mean 300, then 9 likes from 300 readers is 3%. If this number sounds familiar, it's the ratio I gave above for how many I notes I get from my followers. In terms of how engaged the readers are, you're not doing badly. You just need to grow your audience. You get activity and engagement from a critical mass of audience size. And honestly, the best way to get comments is to have something worth commenting on. If you spend your energy first on making your comic the best comic it can be, then people will be pleasantly surprised to find it and do your work for you by word of mouth, whereas if you spend it first on promotion and trying to court "engagement" then you may inflate your subscriber counts artificially, but your comic becomes less art and more "content", and slides off peoples' brains.