I am climbing for quite a while now and would consider myself a beginning-intermediate climber. I feel my technique has significantly improved over the last year. I am very heavy (1,80m and ~100kg) and have large hands for my size, which makes me struggle very often on smaller holds. Even in the level I climb at the moment there are many holds I cannot use which my peers climbing at a similar level utilize without any problems. While I am aware that technique is much more important than strength I feel like my lack in finger strength (in proportion to my weigth) is one of the most important limiting factors to my climbing at the moment.
I would usually agree with this answer stating that "The best training for climbing, is climbing." However, I feel like lastly I made very little progress on my finger strength. I tried to use a hangboard once since these seems to have very little injury risk even for beginners, but was not even able to hold the widest part - I ended up hanging from a big section of the top.
Should I just keep on climbing, or does it make sense to train my finger and grip strength in addition?
Which of the methods mentioned in What hand and finger exercises help with climbing? are especially suitable for beginner / intermediate climbers?