For instance, shouldn't Lord Rama actually be spelled as Lord Ram, because that's how we pronounce it? Why then do I frequently find an extra 'a' at the end in texts?
The final 'a' comes from the original Sanskrit, where the final 'a' sound is known as the inherent schwa. It is not pronounced in Hindi, but a decision was made to preserve the original spelling when romanizing the characters.
Please note that I mean no insult to English here. I know that intelligent people understand this, but some unintelligent orthodox based people would think I am criticising English, so I mentioned no offence.
We pronounce Raama very incorrectly if we pronounce as- 'Ram'. Note that there is A sound(as in 'a'lone) also with M (as in ja'm'). The ma is not 'Maaa' , it is Ma(as in 'mu'mble)
Note that Rama is not Raaamaaa, it is Raama, where Raa is pronounced as in ext'ra' and Ma is pronounced as in 'mu'mble.
So it is better to write Rama as Rama itself. In fact we should write as Raama, but fine, Rama is also okay(though, yet, not correct)
Note that mere 26 letters of English alphabet can never give exact and correct transliteration of what we speak verbally. Even the other characters of Roman script (such as à, è, ñ et cetera) are not completely able to script what is spoken vocally(as phonetics are very limited).