It was even worse than Sinclair BASIC due to the lack of drawing commands (yes, I know you could get these as extensions on a cartridge - I didn't have that). The main issues with Sinclair BASIC were limited functions and the fact you had to use key combinations to enter most keywords.
I also remember it as being slow as all hell when compared to other BASICs, although that might just be the opposite of whatever rose-tinted nostalgia is.
I loved the Commodore 64 but its BASIC sucked. Commodore continued to royally eff up with Amiga BASIC which, if memory serves, was also basically[1] by Microsoft. I immediately switched over to AMOS by Francois Lionet, which was great, although with hindsight wish I'd given Blitz a go too.
[1] Pun also intended, even though dreadful.