To much cap bound up in players not worth their salary to compete. The Lucic deal is of course the worst, but it will cost a lot of assets to dump somewhere. Then you have 4 millions in Russel (Hes a fine defenceman, but not worth more than 2 millions). Sekera is rumoured to be coming back from injury soon and its doubtful he will be worth his 5,5 mill. I would use 1st picks and some young players if they knew they could sign some free agents to fill those spots. Talbot has not delivered this year and they should keep the cheapest option of him and Koskinen this offseason. Lucic, Russel, Sekera and Talbot would get 20 mill of their books.
They have 3 fine top 4D players in Klefbom(To often injured), Larson and Nurse, but they need that 1D to lead them. If they dont believe Bouchard can be that guy getting Karlsson this offseason would make their D one of the best in the league.
They lack scoring depth and its pretty much McDavid carrying the teams offence with some support from Draisatl and RNH. The rest are floaters. Getting one of Stone/Panarin would make them much deeper and would let 3rd liners play in the 3rd line not 2nd. You could keep McD-Drai and have Panarin/Stone carry the 2nd line with RNH.
So rentals at the deadline I would say no, but clearing cap if they are able to dump some players if they know they can sign some free agents would be good.
Oilers should set up the team to compete now while McDavid is at his best, but its already to late for this season I guess as they have to little depth and cant add salary at the TDL.