Fork in the Meditative Road - Concentration vs Insight Practices

The other day I was having an interesting conversation with fellow meditators and I realized that there's a fork in the road for those of us whose meditative path is organized around cultivating concentration in order to then glean insights through vipassana practice. In a nutshell, the fork in the road is that as your concentration gets stronger, you are in a much better position to do insight practices. But once your overall base level of concentration is strong and durable for you shift to insight practices (Stages 7 and following if you're doing TMI practices), you run the risk of losing some of the base level concentration that you achieved through sustained concentration practices. Let me unpack this.
Let's say that you diligently practice and make considerable progress in your base level of meditative concentration. You often reach effortless and exclusive attention on the breath (TMI Stage 8). What to do next? According to some meditation maps, such as the Tibetan elephant map and the TMI map, the answer is simple: keep cultivating concentration until you reach an abiding state of concentration, tranquility and equanimity (Stage 10 "samatha" in TMI). But here's when you hit the fork in the road. It is my sense that once you hit a certain base level of concentration, such as single pointed attention (Stage 8 in TMI), it is skillful to shift your meditation more towards insight practices (e.g., noting, open awareness, etc) . This is, in fact, what some meditation manuals, such as The Mind Illuminated (TMI), seem to prescribe. As such, the TMI chapters devoted to Stages 8 and 9 of that model feature detailed (and very helpful) instructions on several insight practices, ranging from the still point meditation, to choiceless attention, to meditation on the mind, to meditation on arising and passing away and dependent origination.
So it seems that once you hit a certain baseline level of concentration, practice takes a pretty strong turn towards insight. You would think, then, that the emphasis shifts from samatha to vipassana, with the ultimate goal being to reach "awakening" (I won't go into this, but I'm not a fan of the big "A" word and what it communicates). However, the latter stages of concentration heavy maps such as the Tibetan elephant map and the TMI model continue to focus on unifying and collecting the mind with the ultimate goal of achieving an abiding state of samatha and equanimity.
So what's the fork in the road, you may ask? It seems to me that once you reach these latter stages, there is a choice to be made. Does one structure one's sits in a way that is primarily geared towards attaining insight and, ultimately, the "A" word? Or, instead, does one structure one's sits in a way that is principally designed to achieve a more profound and stable samatha?
While these two goals are not mutually exclusive, they do compete for the meditator's time. In my case, I have the luck of being able to sit for 2 hours straight, which I do on a daily basis. You'd think that this is more than enough time to fully cultivate both samatha and insight. But I actually don't think it is. In my case, I spend the first 20 minutes or so settling in, primarily doing "Do Nothing" practice. I then shift to 20-30 minutes of classic mindfulness of breath practice. With a more collected mind, I shift to Jhana, during which I go from first to fourth Jhana, then back down and back up. This takes another good 30 minutes. Upon emerging from 4th Jhana, I'm left with about 40 minutes, which I then fully devote to some kind of insight practice (I rotate between still point, Do Nothing, Self-Inquiry and Shinzen style noting). This may seem to be enough to fully develop samatha and vipassana, but I've noticed that with this approach my concentration practice isn't getting developed as much as my insight practice.
In a nutshell, my concentration has gotten weaker and more effortful. While I used to reach effortless and single pointed attention on the breath (TMI Stage 8), I now only reach such concentration intermittently. Interestingly, however, at the same time that my concentration is getting weaker, a host of insights are coming at me right and left. As a result, my sense is that if I'd like to continue making progress along the samatha path and ultimately reach an abiding type of samatha and concentration, I would have to devote way more of my sits to anapanasati (mindfulness of breath) and Jhana and less on insight. Thus, the fork in the road. Should I prioritize cultivating samatha over vipassana or vice versa?
Right now I'm prioritizing insight over concentration practices, since insights have been flowing quite nicely once I developed enough concentration for single pointed attention and started shifting my practice more towards insight. But it feels that by doing this, I'm getting farther away from achieving full samatha. I sometimes wonder if this is the right call. It feels like it is for me. But perhaps others would make a different choice.
Much Metta to all, and may your practice continue to blossom and mature!