i have a bat myself and its big enough inside to hold more than a grams worth, mine funnels pretty small and while i do occasionally catch some debris in my mouth it doesnt bother me much.
most bats just have a bowl in front while i can use my piece to hold joints and blunts so

for me using a screen would only be hassle once it becomes too dirty to pull thru as id have to use some sort of poking tool to dig it out

and its also a color changer so im not tryin to scrape along the sides and lose the coloring

my advice is to not let the debris bother u and get use to it if u plan on using the piece

plus since i cant really see inside anymore i know i smoked it all once i suck in some ash