I am a native English speaker, and I also speak Spanish with a decent accent having lived in Spain for years. For example I know how to roll my 'r' letters the Spanish way.
I have decided to learn Russian from scratch as it will be a huge help towards my future career. Many people have said that learning Russian will be easier, as I can pronounce some of the letters which are similar to Spanish.
From my experience in life, I also know how to learn a language by repeating words/phrases, but also by studying the 'boring' grammatical rules.
I was wondering if someone could provide some type of benchmark, given my capabilities and experiences listed above, as to how much there is to learn in Russian compared to Spanish? For example, if Spanish had 100 grammar rules how many does Russian have? I have already compared their alphabets where Spanish has 27 letters, as opposed to Russian which has 33 and are mostly different to the Latin alphabet.