I don't want to "lengthen" time, because it significantly lowers the frequency, from about 1mhz to 200khz, which is bad. I've found a partial workaround - I've inserted

Code:
PORTA.2=1
PORTA.2=0
PORTA.4=1
PORTA.4=0
16 times, so now having about 90% duty cycle, which is ok.

But, is there a way to fix this otherwise?

Try 18 series PIC, or 24 series?