I'm concerned as theirs a severe lack of options with the ezy to builds in relation to weaponry,
Well in this case, the Suppressors and Infiltrators only have one weapon option in the rules anyway, and no options to give Sergeants wargear. The Infiltrators even come with an option you can't get in the multipart kit, which is the Helix Adept. The only thing you miss out on is the Comms Array (and I guess the option to build Incursors instead, but if you want Incursors you wouldn't be considering this box for that anyway.)
The only place you're really going to notice the lack of options is on the Eliminators which come with Bolt Sniper Rifles, whereas the multipart kit allows you to take Las-Fusils instead. That may be a consideration, although it could be argued that the Bolt Sniper Rifles fill a particular niche (taking out support characters) that isn't really covered by much else, whereas the Las-Fusils provide anti-tank fire you might already have covered by other units.