I would agree that the books by Adrian Goldsworthy are my "go to" for information. I also have Peter Connolly's "Greece and Rome at War" which is a bit dated but good for general information.
My own legion is modelled on Legio VI Victrix which served in Britannia and my version is roughly 1:20.
https://leadadventuhttp://leadadventureforum.com/Smileys/frankenstein/cheesy.gifreforum.com/index.php?topic=121726.msg1607492#msg1607492 The legion so far - I still have the baggage train, Legionary cavalry (
eques legiones - 6 figures), the Legate's bodyguard (
singulares legati legionis - 3 figures), some engineers and other immunes (heavy artillery, medical, etc.). And maybe an elephant. Claudius brought one. Though Polyaenus was describing Julius Caesar's raid he was probably confusing it with Claudius' conquest in 43AD.
"Caesar had one large elephant, which was equipped with armour and carried archers and slingers in its tower. When this unknown creature entered the river, the Britons and their horses fled and the Roman army crossed over," Polyaenus, (VIII, 23.5).
Note that the Nubian light infantry are "generic light infantry" and not part of the legion for Britannia.