Frustrating, realistically the options laid out forced you to max out certain skills and completely ignore the others. Infiltration needs to be maxed out from the start regardless what route you take, combat and perception are also maxed early followed by athletics, then guns get the remaining points to end off at 5.
I managed to get to mission 6 before realising there was a re roll button which helped somewhat with the frustration levels caused by restarting multiple times due to duff rolls when "you need a 4 or higher" and use up two re rolls.
I would have preferred it if there was more options like Julian724 said as it forces you to use skills you may have never intended to use.
I found electronics, explosives, mechanics and sniper pointless skills as the "main route" never really needs them at all. you can make it from start to finish with only doing one mechanics check and even if you fail it doesn't affect the game (don't know if that was intentional)
Its a luck based game and would be more enjoyable with more options focusing on choices you think your skills would be good at rather than having to play a certain way the game forces you to.
and finally i think if you failed some rolls it should allow you to try different things, i know there was some aspects of this (like dodging bullets and trying again) but I think it would have been better if you did it more often especially at the start of missions as there was a lot of "mission start - make this roll... failed? well you lose"
Overall a frustrating time waster but could be made enjoyable with maybe a skill tree system that unlocks options rather then randomised rolling. but that's just me.
If you are intrested in my route, it was
(Go inside - 4+ inf) (4+ inf - gun down (12+) *if failed roll dodge and then try on 13+) (crowd shot 12+ guns) (6+ Inf) - (3+ Per - 3+ com) (7+ per (sneak) 6+ Inf, 2+ ath) (16+ electronics *that i fail*, 8+ inf, 2+ ath, 7+ Inf, (climb) 4+ ath, 7+ inf, 2+ com, 6+ inf) (10+ inf (follow) 10+inf, 5+ guns)
as you can see that's 10 rolls on infiltration (most of which can't be avoided) 3/4 guns, 3/4 athletics, 2 combat, 2 perception. If you want to do something like this again I would strongly recommend giving the player more control even if it means more work for yourself making it.