C-44, Eclipse and Oppressor have quicker draw/stow/ADS, and you can move faster, i like SMG/Carbine but in ED-O they have more cons that pros, base range of 25 m like pistol cripple them.
Movement:
here a quick compare, in blue for Suits equipped with Combat Movement Speed, tbh just stow your weapon or draw your pistol/shotgun if u need quick redeploy.
Handling:
put
Fast Handling on you prefered weapons and you can draw/stow/ADS at almost same speed of SMG,
to compare Carbines to Rifles, higher RoF + lower dmg/shoot of Carabine is outperformed by Rifles range with almost same damage ratio (bullet dmg/RoF) up to 50m for AR50 and 70m for Aphelion, base range that you can extend with Greater Range.
Personal setup for High-Intensity GCZs,
i have alot of fun with Aphelion, Intimidator, P15 setup to maximize flexibility at all ranges and movement speed.
Fast Handling, Stowed Reload, Magazine Size just to forget reloading and keep sustained fire;
Greater Range on P15 to bring the effective rng to 38m; remaining slot on primary as desired.
P15 in combo with Aphelion, do not think P15 as sidearm/backup, this little beast is a real damage dealer and almost hitscan,
Tormentor is the king of dmg but slow plasma bullet speed do not match with Aphelion for long range hit, i prefer Tormentor on missions, while P15 on High-Intensity GCZs, personal choice of course.
Intimidator when things come close and personal, w/ max movement speed, what else
GCZs Wild setups,
For extra fun in GCZs, "double shotgun" or "double L-6" is alot of fun... P15 still my sidearm to quick "coup de grace" wounded NPC.
Final considerations,
it should be noted that "switch speed" is stow of active weapon + draw of selected one, is almost negligible in tens of milliseconds, but if you go for Fast Handling is better to have on all weapons, of course the ADS bonus still applicable on single weapon.
SMG need some rework & love, especially the "not-so-oppressor"...