I travel a lot in trains, so I just want to share my experience with you.this is whole summary of train journey
First of all, IRCTC is know for its continuity, same disgusting food each and every time whether its lunch or dinner(breakfast is different from dinner and lunch but still its same breakfast for 365 days), it doesn’t matter whether you are travelling after 1 year or 1 month you can actually guess the food menu .its going to be that same old same old
Now lets come to quality of food, yes I agree the quality of food slightly increase from bad to good .but if you are travelling for three days and eating the same thing for three days then its going to scale it down to worst
generally I travel in ac compartment so I can’t give you review about the problem you faced in sleeper(toilets, seats.mosquito and other problems)