Used to train in southern taiwan as part of Ex Starlight (Singapore) and we do shared the same training area with ROC Army and interacted with some of the ROC soldiers.
Taiwanese army used to be well disciplined, tough and well trained till the 90s. 2000 onwards everything started to change for the worse.
As the 2 political parties campign for votes especially younger voters, national defence gave way to populism.
As a result, Conscription was reduce several times and by 2018, recruits only needs 4 months basic training. Discipline seems to be a problem with abolition of millitary law and court martial.
The desire for Taiwanese youth to fight war is very low. Most harbour the hope that American will fight for them. As a result there wasn't enough regulars to fill in active combat units. Lot of units were 'empty shelves' that severely under strength.
As for millitary ops, most difficult part should of the campaign is beach landing. Not many areas on the island is suitable for amphibious operations. It will be good if china can find a way to demoralise the enemy before actual landing.
My thought is they might want to take Penghu island first which sits strategically between Mainland and Taiwan.
Historically Penghu served as a springboard to invade Taiwan. Winning Penghu means half the war won.
In todays context, it might not served much as springboard but fall of penghu will dealt a heavy mental blow to Taiwanese morale. It also serve as a decoy to confuse the enemy where the actual landing site will be. It opens up the possibility of 2 landing fronts. Enemy force will spread thin as a result.