Nah, a weapons team army is still one of the better armies skaven have, it's just not the be all, end all that it is in vanilla. Jezzails still wreck monstrous infantry and SEM/characters, while Ratling Gunners have the suppression contact in order to slow whatever slips by your summons.

However, I highly suggest using only a Grey Seer of Plague with the Seeping Putrescence trait, 3 Plague Priest, and 2 Warlock Engineers as part of your character set-up. Warlock Masters just aren't worth using in this army. You really want a double dose of Triangulation and Arms Dealer for best results, and 2 Engineers will cover your whole army with the Extra Powder passive aura and Ballistics Calibration activated aura.

You'll also want to horde Crowns of Command for that army, as Poison Wind Mortars and Plagueclaw Catapults do a lot of the heavy lifting, and bombarding your own summons is the best way to kill infantry. Mortars do most of their damage via their contact effect in SFO, so you need to micro them pretty extensively in order to get the most damage out of them.

Also, don't be afraid to utilize the Ratling Gunner/Jezzail actives. It damages the whole unit equally, so if they don't take any damage from any other source, they won't lose any models, and the damage will heal after battle. This can let them turn what would otherwise be a rough battle into a route if used wisely.