Daily suggested workout - half marathon plan

hi! I recently bought a forerunner 255 and am liking it so far.

I am running a half marathon in May and wanted a plan to use to train towards it. I decided to use the Garmin coach (DSW rather than a plan) as what I’d read here and elsewhere seemed well suited to me. I started in early Jan as I wanted to work towards it slowly (my first/last HM I got injured in the final 4 weeks pre race -probably due to increasing load too quickly).

I followed the base phase probably 80-90% - it was fine but I got quite bored of all the 30-45 min slow runs. So I was excited to start the build phase (this week) and aside from a couple of tempo sessions, all the other runs I can see are at the same slow pace still. For info, my goal is 1:50, so a 5:15/km pace and all my runs have a target pace of 6:15. Am I being impatient or does this indicate it thinks my goal is unrealistic?! I’d like to try and meet my goal and think it’s doable with my fitness level. Has anyone else experienced this? Should I stick with it or try to increase pace for some runs?

Side note, but the only thing I don’t like about the coach is you can’t input other training needs. I swim with a squad 2x per week which is quite intense, and so my plan is often unrealistic for me on certain days and I need to select different workouts. I wonder if this will have a long term impact on my goal