Advice for indoor veg outdoor flower( first grow)

Hey guys I'm planning to grow two plants for my first grow and I would like to veg indoors and flower outdoors. The strains I'll be growing are KC Brains KC-33 and Northern Lights as I hear these strains are very resilient and great for first time growers. I'm going to veg 18/6 for atleast a month to two months. My indoor lighting setup for veg is as follows:

1x65W CFL 6500k
4x20w CFL 6500k
1x100w HPS

I'm unaware of the colour temperature of the HPS bulb but I hear 6500k is optimal for vegging, if the HPS bulb turns out to be below 4000 would it still be a good option taking into consideration I'm planning to flower outdoors?

For air circulation I'm going to have 2 80mm exhaust fans.

Now for soil I'm planning to use a cheap potting mix for the seedling stage and gradually add seasol powerfeed. However when I'm flowering outdoors I plan to mix native soil with premium potting mix which contains compost, manure, fertiliser and trace elements in a 5 gallon hole. The site I'm flowering at is a floodplain near a river, would this be optimal considering I'm mixing native soil? I hear floodplain soils are very fertile.

My goals are to maximise yield while keeping things as simple as possible while ofcourse making sure my plants are healthy. I feel like my soil is not so great and that I should dig a larger hole for outdoor flowering. However I feel that most soil mixes have too much fertiliser, is it not enough to have NPK present along with trace elements ? I've seen mixes that include different types of manure, guano, compost, kelp meal, bone meal etc in the single mix and to me it seems like its unnecessary. However I'm still a newbie and yes this is my first grow so it doesn't feel like I can make my own judgement on this.

Any advice is greatly appreciated thanks!

the HPS most likely have a Kelvin color between 2000 and 3000K (my old HPS is on 2100K)

but perfectly fine to use along side the 6500K CFLs I know a lot of Ppl. swear to 6500K in veg but if I had to choose only one I would actually pick up some 5000K bulbs or like I run now in my T5HO fixture a mix of 6500K and 2700K, plant need all colors of light all grow, just like/use more of the blue spectrum (high Kelvin colors keep more blue and less read and vise versa) in Veg and more of the Red in flowering (outdoors it adapted to the seasons as the sun stand in different angles on the sky and let more blue light in spring and more red in summer/fall)

about your fan`s dunno if it will be enough, for fresh air (Co2) it probably be fine, to cool a room I dunno, up to your ambi temperatures in there and how much the light warm it up, need to try and run it to see if you can keep them 20-30C they need to thrive with 24-26C as optimal (76-78F)

don't cut corners or go cheap on your soil, give em a good start, your job now is to give em a good head start, and 80% of that happens under the soil
I dunno what season power feed is ? but if you use a good soil you don't really need to provide small seedlings and young Veg plant with much other the water, in the holes you plan to plant em in I would for sure add some rich soil or some nutrients sticks/ball`s

I'll be growing inside a closet do you think the fans are sufficient to cool a closet though? I'm looking to buy a 400w metal halide lamp but I'm worried about heat within the closet, if the temperature within the room was about 24C do you think a metal halide would begin to raise the temeprature too much? Thanks for the feedback!