We have been playing starfinder in fantasy grounds for maybe a couple years. We also play dnd on alternating weeks.
So, here are my thoughts:
1. I really enjoy starfinder. The different races and classes and themes give unique feeling characters and tons of role playing options, although there are a few weak spots / overpowered options. A solarian operative who can explode for 80+ damage and do 30 damage without breaking a sweat AND has hit points to spare just makes my mystic character feel bad when a spell finally makes it past a saving throw and does...3 damage. oh well.
2. starship combat flat-out sucks and feels like 1970s star trek era nonsense. paizo needs to get it together and rebuild ship combat from the ground up. we don't use it AT ALL in our campaigns.
3. despite what you may be hearing, there are very viable mystic builds that are super fun to play. yes you want mystic cure and mind thrust. however my character took long arms proficiency and another damage boost so that I can reliably assist in combat without burning all my spell slots. force disk is not bad either. the thing to emphasize is that this is a tech-based world. Don't hesitate to get cyber enhancements or necro grafts. get weapon fusions and fusion seals and get as many spell gems/ chips as you can afford. I think using tech to supplement the low number of spell slots was the original idea. Give some of these as quest rewards to let party learn about them. i am a paranormal investigator mystic, which works out really well for our current campaign.
4. i wish there were more party buffs for the mystic to use. wisp ally is good at low levels though.
5. flanking /advantage is not a thing which is dumb. highly recommend using some house rules in order to get people interested in a bit of strategic battle planning.
6. cover is a thing so make sure you provide cover in every encounter
7. dealing with a single hidden sniper is super annoying due to all the rules about difficult terrain, climbing, etc. try not to TPK your crew if you get in this situation.
8. ammo usage can be insane on some guns / character builds, but the conserve fusion can counteract this
9. low level pistols suck and should be avoided. however having a low weight decent pistol (like costs more than 4K) that uses a different ammo type than your main weapon isn't terrible for a long dungeon crawl if you run out of ammo. however, some character builds can recharge batteries for energy weapons so make sure to do that on long rests. Be very careful about bringing non-energy weapons (projectile for example) on a long journey because you cannot easily get more ammo in a jungle or asteroid.
10. ALWAYS TOSS THE ROOM AND SEARCH THE BODIES.