thanks, that picture is looking a bit messy was digging quite a bit of composting holes then, actually have quite many more areas where bananas are. Planted about 20 different kinds of bananas, but have only identified about 6 kinds so far, I didn't bother labeling anything...
Long story short, I think your spacing in that planting area you have is absolutely perfect for Gros Michel, you can try to wait and see if this goldfinger will produce as a solo tree and then remove, by that time you will have another gros michel sucker to put there. I find that the Gros Michel will only produce 1 or 2 good suckers. So is very manageable in areas where you just want 1 tree at all times Which is how the planter should be in my opinion. 2 trees with 2 suckers each, strongest kept when ready.
Also Cavendish is similar in growing style to Gros Michel, and produce very very large racks as a solo planter, but many people complain about the taste. Without 'gasing' they ripen very quickly with green skin, but taste is still very good.