I can see them grabbing maybe one or two players to fill in roster holes after a busy offseason but that would be about it.
Look at the math: They'll be drafting 30 players in the expansion draft. With a 23 man regular season roster that leaves 7 who will either be traded or sent to the A. Those guys who go to the A will probably have to go through waivers. There's not a lot of room left for waiver claims unless they find themselves short a player or two at one or other position.
And 7 players in entry draft. Plus whatever CHL and college undrafted free agents they might sign.
Plus whatever players they acquire from future consideration trades (or the picks that result in players).
(Less any players traded away.)
You need call ups (signed to NHL deals) for depth when injuries happen. (Sharks have called up 10 different players this year, but Vegas might get by with fewer.)
23 NHL roster (2G+7D+14F)
AHL-eligible for call ups (1G, 2-3D, 4-6F) (prospects, journeymen)
Plus building depth in prospects (to get closer to the 90ish limit of depth chart including all players on NHL, AHL deals, plus unsigned draftees). Guessing that 6+ players drafted and/or from future consideration trades might be "prospects" that are in college and/or junior so won't be under contract either.