Rockwool blocks on top of rockwool slabs is the only way to go. You're not going to be vegging plants more than a couple of weeks. They are not going to be able to pay people to transplant cuts into coco, potentially twice, or dispose of it and thoroughly sterilize the containers at the end of the cycle. On top of the financials anything but rockwool gives you more of a potential pest headache.
Definitely the most important details for you to get right follows...
Make sure you're building a space that provides an area that's positively pressured for your crew to shower, change/store belongings and wash their clothing. They should be told to wear clean clothes that haven't seen their home grow in and expect them to be washed during the shift for them to wear the next day or to wear out after a shower if they so choose. They will only be able to wear clothing that has been washed on site/shoes that stay in the building, after they shower, with a disposable suit or washable coveralls. Look into an air shower.
If any of the above gets any flak based on budget or necessity, walk away, these people will fail just fine without you.
Design your space so it's impossible for someone to go into the wrong room based on a day's work flow. You should have a veg crew and flower crew to limit cross contamination and put your aces in their places.
Have several smaller rooms/tents for R&D. Keep them in your veg space, if possible, to prevent possible pollen contamination.
Your flower crew is mostly going to be low skill, low knowledge people being led by yourself or someone whom is working in lockstep with you. Don't be afraid to hire the guy that will replace you, you're going to need someone who is a maverick on your side to keep YOUR job.
The veg crew is going to need to be very strong, people that have an eye for detail and actual abilities with extensive knowledge on strains and horticulture. If you were going to do coco anywhere, your mothers are the only place I'd use it. This is probably going to be an older person that requires a higher rate of pay and might take some finesse to get on board with your SOPs. Again, don't be afraid to hire top notch folks. This person or people might be able to help you tighten things up, take feedback and carefully consider whether they have a path to improvement.
Look into a water ionizer for ipm in flower. Alternating between high/low ph water should kill any pathogens and not allow a pest population to get established.
This is a game of seconds, you're going to want to make things as streamlined as possible from the get go. Sounds like the other location's crew might be able to help you out with this.
If you have any questions feel free to pm me.
