Is there increased risk at first solo? Of course. How could it be anything than other than that?
So, are we hitting on anything in particular here? (e.g. what does the industry, and customers with hindsight, agree are the minimum excercises?).
[me personally, #1 was fine, #2-5 all had some issues ranging from gusting x-wind, to spiral dive, to... well, I learnt alot early, scarily...]