You run into several problems with that.
While a "military culture" could do much to improve the Russian Army, the vastness of the land and "small village nature" of the conscripts is a big obstacle.
Than there is the industrial side. The Russians seldom lacked in morale and willingness to lose man, but material was an other matter. The industrial muscle was not there. And if the muscles lacked, the arteries (Railroads) were few and far between.
So where do you get the money?
And more importantly, if you use German Trainers, that implies some sort of positive relations between the Countries. So a Franco-Russian Alliance is harder to acomplish.
Also the British would see the better Russian Millitary, be it only Army with or without the Navy, as a "Existential Threat" to India...
How would you try to solve those problems?
I thought that Grand Duke Konstantin Nikolayevich of Russia, N.N Obruchev and D.A Miliutin would be enough to reform the military, especially if I modified the Memorandum of January 1873 named "Considerations on Defense of Russia" as a massive construction of military railways and roads was planned in this memorandum, but never implemented.
My idea was also to make military service compulsory for all 20-year-old males (рекрутская повинность) with a few exceptions. Of course, voluntary recruitment would be different and similar to the enlisted and professional soldiers below.
Males would serve three years in active army and seventeen years in reserve (landwehr). After the three years, males who wish can become enlisted soldiers and continue to serve in active for seven years with a salary and later stay ten years in reserve (landwehr). They can continue to serve after their ten years in reserve and become "professional soldiers for life" with an higher salary, if they wish.
The system of military education would also be reformed, with lower secondary education made available to all the draftees in military schools during their three-years term and tertiary education made available to valuable enlisted and professional soldiers during their terms. Then, you would have "draftees" (three years and seventeen years in reserve), enlisted soldiers (ten years and ten years in reserve) and professional soldiers for life.
"Draftees" could climb the ladder up to NCO's, while enlisted ones can enter into the first parts of Officer corps and get social advantages at the attainment of a specific officer's rank, as an incentive. They can also get a low noble title, if they move high enough. Professional soldiers can move higher.
I will have to read Strategy and Power in Russia 1600-1914 by William C. Fuller again. On which model and by which advisors was Russian military reformed in OTL?