I'd suggest slightly larger images, I'd say 480x480 minimum, I tend to do 640x480 as smallest myself. This reduces some of the 'negative space.'
Center images by putting center tags around the image, for example: <'center> image link <'/center> [NOTE: remove the ' in those]
On the lines you start with *to add emphasis...instead use ** before and after to bold it instead for example: * * bold * * without any spaces between them = bold
it gives the emphasis AND makes the post more scannable :)
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