Yes, quite a bit happened.
I have not covered subjects which have been covered in detail:
- Was Ney given orders to take Quatre Bras before the morning of the 16th? (I think yes based on the actions of Guard cavalry and Lefebvre-Desnouettes's dispatches - but good arguments either way. Taking it could have had dramatic impact on campaign, but at time decisions were made, this was not known... and as I tried to document, it just wasn't the Prussians in the right rear that were constantly on the French collective mind - the left wing was sticking out in space while it was known there were anglo-dutch forces in the left rear with an ample possibility of a concentration there. There has simply been too much analysis of this campaign with perfect intelligence. When one studies the map with only French forces and hypothesizes where the allies could have been, it is not so clear. Imagine a right wing (with Napoleon on left) that has a spur out to Gembloux - had that happened on June 16th with more aggressive operations that pushed Zieten back, it could have been isolated and eaten by the unexpected arrival of the Prussian army. Also note, Napoleon judged Wellington and Blucher correctly in many respects, and hence he might not have been concerned about pushing into Wellington's area aggressively, but Ney and especially Reille obviously thought differently.)
- The diversion of d'Erlon to Ligny - a product of the documented confusion, the details are but a curiosity.
- French operations 17/18th - had only they started at dawn and were aggressive - yes, a totally different campaign, but I am more interested in the hypothetical of had Napoleon's original plan been executed. I think d'Erlon/Ligny will forever hold the imagination. Just hard to compete with dramatic big battle.
- Combat in general - the modern historian, relying on the memoirs of the participants, has done a great job capturing the experiences of the soldiers etc.
About those French operations, I find that many many many have dissected the various movements to the foot and by the second for the 17th and 18th feeling it was there that the campaign was lost.
Where is this analysis from June 5th through the 16th? Of course on the 16th there are those that devote detail to elements of the French operations, but usually d'Erlon without looking at the picture from the 15th and capturing the root cause of the problem.
Interesting tidbit about 17th: Grouchy was given a written order - but at what time? Noon? 3pm? In 1840, this order, long denied by Grouchy, was printed by a printer named Bauduin in Paris, dated at 3pm. In the year of Napoleon's remains returning to France, who was trying to influence opinion?
Napoleon had been ordering Ney since the morning to engage what was in his front (Wellington) while Napoleon would move up the Nivelles-Namur road and engage on the flank. Ney did nothing, and said he had heard the Prussians had been victorious. Egads, the communications from and to both the left and right on June 17th were horrible - who to blame? Everyone. Soult's morning letter all but admitted he hadn't notified Ney of anything.
And no theory I put forth should ever be read to suggest that I believe Soult was a good Major-General, or remotely in Berthier's league. I just believe one can be mediocre/poor at a job, and also perform intentional bad acts.
Net result was that Napoleon ended up taking charge and leading the pursuit - Wellington didn't wait around to get attacked. Rain started early afternoon and lasted at least 12 hours. Pursuit is another one of the underwritten elements of the campaign, but apparently it was lively at times. A the Mont St. Jean position, Napoleon deployed some cavalry and artillery and got a sufficient enough response from the Anglo-Dutch forces that he at least knew they had stopped.
Some argue that Napoleon absolutely did not think there was going to be a battle the next day, but the correspondence suggests otherwise - that he felt it was possible and sent out an order of battle that was referenced in the next day's order, and by Reille in his contribution to Ney's Documents inedits.
And then Napoleon began to plan the next day's operations - which the conventional history suggests was to largely not send Grouchy any correspondence and let him drift in space...