British army in the Crimea did manage to stay in a battle-ready shape throughout the campaign
A lot of the failings in that war were due to logistical issues. Sanitation? Well, that was in the dumps for most nation's militaries and the brunt of it would be borne on any soldiers on the march. Really only the French had gotten this right yet and on paper the Austrians, although they didn't campaign so I don't know if camps would be built to regulation in practice.
The charge of the Light brigade? This is often stated as a prime example of Aristocratic buffoons not understanding war. Well, I'll admit the order of "Lord Raglan wishes the cavalry to advance rapidly to the front – follow the enemy and try to prevent the enemy carrying away the guns – Troop Horse Artillery may accompany – French cavalry is on your left. R Airey. Immediate" didn't take into consideration of the recipient's vantage point. However, Raglan's intention of trying to keep the Russians from carrying away guns seems to make logical sense. And I don't fault Lucan or Cardigan for sending their cavalry into the meatgrinder. The order of "immediate" implies no time to waste and from their vantage point the only guns are the ones they sent their cavalry into. I don't really see anything wrong with what these officers on the receiving end did. They knew the cavalry would be mauled, but when you get an order like that you have to assume it is part of some grander plan that makes the sacrifice worthwhile, not that your superior is General Badtaktiks.
I don't think the Crimean War was an example of the best generalship of the British Army, but it seems "adequate" to me and certainly better than the American Revolutionary War. General Howe had to find the longest way to reach Philidelphia, in fact even his subordinates pointed out it was faster to go by land. In the ARW, George III thought this was the failures of individual officers and you are going to have them in any system, not that the system was really bad. But suddenly in the Crimean War it's the system at fault? That was puzzling to me.