The chikorita line has held quite the place in my heart for being so bloody adorable when I first saw it in the anime, and was a bit further cemented in terms of sentimentality when I got it first time around as my player avatar back in Pokemon Mystery Dungeon Explores of Time and Sky the first time around. Coincidentally, mudkip was the one I got in the last two games twice as well in terms of being the "calm" archtype.
In any case, the little dino plus bayleef grew on me. Megenium however, while not terrible... Eh, it feels sparse. A missing, beautiful head leaf plus the red eyes just makes the design seem off.
I've looked high and low for some alternate design for the meganium mon, but the best I have ever been able to find was just putting the standard old head leaf from the second evo on top and call it a day. At least it doesn't leave it bald, but I end up being fed up to the point of making my own shitty sketch of what my hypothetical third evo would be in a mon called strigaleaf. Nothing much but a dark/posion kind of mon that has more bite than your average meganium, but utterly uninspired besides that. Making decent evos is hard to say the least, but a man can dream.