Gridless is too hard. Optimal path is to curve around enemy bullets if possible, and you need a program to curve around for you for max distance. Too much to deal with for the player. How about a hexagonal grid, then?
A UFO (not to proportions). The hexagon is the hurtbox.
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Yggdra on a UFO.
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The hexagon outline can flash/glow to make it more obvious. Or the grid layout can be overlaid on top (maybe toggled).
The Kitt3h sees all. And aforementioned Kitt3h will nom all if he so chooses.
Roflcopter soi soi soi.
Kitt3h nom nom nom.
...So, got any fud?