Shaka : are you doing that with pax on board? I find hard to believe you're flying a 737 ,in uk,actually I believe you're flying it on FS2000.No real airline pilot will do the trick you've just described.
LVL CHG slow? Try engaging it and reducing comanded speed at the same time. Gee..I'd like to have you on my plane,sitting on the last row while I'll perform the 'avoiding wx' maneuvre you've just described.