It is normal to use external graphics and playout solutions in a live environment. Maybe give propresenter or CasparCG (free software, developed by swedish television for its own needs) a try.
ATEM Software is "only" a controling Software for the ATEM hardware. So it can't be compared with VJ-Software, which porcesses the whole video-workflow inside one computer. The ATEM istself don't have the technical design to do more than "swiching". But there is a Photoshop-plugin, which allowes to send graphics direct into ATEM mediastore.
If you compare the possibilities of an ATEM with other systems like Tricaster, please compare also the price.
I decided to use a CasparCG for my live-sports-streams. It works like a charm, but needs some preparation and training before use.
The price for this additional PC is less than the difference between ATEM and Tricaster