It took me a good 2 seasons to get my arena up to scratch. Remember if you keep winning and progress up the ladder each season you will keep getting more people turning up.
Arena = long time progression
You don't want to spend all your money and not be able to pay your players.
To do single pos training you have to be prepared to not play players. The easiest way I found was the following.
Only put 1 player in a position (say pg) per game with NO reserve or backup. This garuntees 48 minutes in that position. When I entered this league I bought 3 old but higher skilled players to keep me competitive, it's different now with a higher quality of teams but youngins are where your long term strength comes through.
As you would have seen my Pg Neil is the strongest in the league but it has taken 5 years to get him there and he is still improving. I wish you luck because blue side is 3 times stronger than 4 seasons ago when I entered but it is still one of the most active
When the Beasts Roar all in the way shall be struck down!!!!!