It is pretty obvious that atm the levelcap is there because the features for lvl5+ are not ready.
Yea i was pretty sure this was the main reason its not 5 or higher as well - now we also got confirmation for that (see above).
ANYWAY
Id like to hop on this thread and ask wether or not increasing level cap to 5 or 6 (since 6 doesnt require introducing another full set of spells - should be doable? not sure what the list of class features looks like around level 6) is something you generally *want* to do or if EA is never going to past 4. I was intending to hold back on playing until a level cap increase (even if its in 6 months or something) but i dont actually know wether or not one is coming in the end - and lord knows i could use a great game until november since PC releases this year have been less than stellar.