Good point, Jubal. The orange bug is based on the crab (armour and gills) - which I think you've pointed out with the shields. Btw I've taken the shields out of the game to reduce the number of powerups you can collect in the game. There was a bit of confusion on how they worked, so I decided to consolidate the options.
I've tried a number of new features over last 3 months. They included a rework of the levels (so that there were 3 smaller levels with varying difficulty) and giant spiders. I've pulled this work out because I feel I need to simplify the game instead of making it more complex. I've even pulled out the canvas for now. Btw, I have mixed feelings about the levels atm.
I think the aim now is to lock down Postbug and release it on a number of platforms. If I get enough interest, I'll then look at extending it. Your suggestion of different bug types to play is at the top of my list of new features.