There is an Economist or Atlantic article written in the 1850s floating around my office that discusses the problems of the Russian army in the Crimean War and it reads exactly like what is wrong with the current Russian army.
One of the other things that resonates with me about the Crimean war is that it may be that portable anti-tank, anti-air systems and long range A2 (anti-access) weapons may well be taking us back to the age of rifles which began in Crimea, was manifest in the US Civil War and reached its extreme in the trench warfare of WWI in which the defense had the advantage over mobile offense.
Now alternatively, the systemic advantages the Ukrainian army has (better leaders, better cohesion) may negate the dominance of man-portable defensive systems. Also, we (yes we) have the advantage of our superior information integration systems (i.e., RIVETJOINT, AWACS, drones, satellites and our network of trained operators) in which we are capable of destroying defensive systems faster than they can be deployed.
Now to take the lab coat off. I'm definitely rooting for a rollback of Russian gains and to have them bled white so that Putin loses power.