I don’t think another polysynth is a bad idea at all if it fits an area you don’t have covered. I have a Prophet 10, a Trigon 6, and a Take 5, and the Take 5 is a great analog synth with an extremely robust mod matrix, which is something it sounds like you may not already have (I don’t know what an A4 is, though, so maybe you do). I would say the Take 5 is kind of like a smaller Rev 2 with VCOs instead of DCOs - it has that same crazy mod matrix and the wave morphable oscillators. I had a Rev 2, and I sold it because I already had the Take 5, which I ended up liking more (I still loved the Rev 2 - I just have limited space and funds, so I sold it and got something else). But I still kept the Take 5 when I got the Prophet, which speaks to the niche it fills.
OH! Also, the Take 5 has a Q compensated filter, so it retains everything when you crank the resonance - that is another thing that makes it unique among Sequentials.