Need Breaststroke advice and workouts

I'm trying to make a qualifying time in either 50 or 100 *** for the SCY Nationals and need some training help. I've posted my goals on Ande's thread, "what are your goals and what are you going to do to get there" but they are essentially going from a 35.xx to a 32.xx in the 50 and a 115.xx to a 110.xx in the 100. I have a great Mon-Wed-Frid, coached, 90 minute, interval-based, workout that is IM mixed, 3400-3800+ yards. Right now we are building endurance without much sprinting and not focused at all on the breaststroke. I am lifting weights (with a focus on my core) tues-thursd. Occasionally, I have had a technique consultation from a private coach and am working on my stroke when I can. I'm going to try and post a video as soon as I can, as I need a lot of help - my size (6'-3'') and build (190 lbs) can only get me so far. I've only been swimming 17 months and I'm 43 y/o. I want to add at least one other swim workout per week, but need to know how to structure the workout to focus specifically on getting faster and stronger on the breaststroke. Does anyone have any breaststroke-focused workouts to recommend, including drills, sets, pacing ideas, etc? Or any other suggestions? Many thanks for all ideas!