I played around with this sort of thing last night quite a bit last night while half-watching Monday Night Football. This is for a H2H Categories league (probably less effort would be needed for a points league).
First, I have a Rotowire subscription and manually entered in my roster onto their platform so that I could utilize the lineup optimizer. However, that’s just the starting point since it doesn’t take the constraints of daily lineup into account or categories.
What I wound up doing was creating a spreadsheet with two tabs. First, “Week 2 - Plan” includes a column per lineup slot (i.e.,  G,  F, C, G/F, F/C, UTIL) and then a row for each game that I filled with the player’s name and day of the week in parentheses. Some of the assignments were obvious (e.g., start Giannis four times this week!), but some of them required some consideration.
Below that on the same sheet, I have my potential bench players as rows and day of the week when he’s playing as columns. That way if for example Rozier isn’t available Wed/Fri/Sun either (he didn’t play Monday due to injury), then I can figure out when I need to start playing Powell or Poole and still make sure that I can cover the three games that I had hoped to start Rozier in. This is duplicative of the “Schedule View” on the platform, but I wanted those data alongside my lineup plan.
Second, I created a “Week 2 - Projections” that included the daily projections from Rotowire for all of the players that I’ve got tentatively included in my lineups (this involved some CSV exports and vlookups). I then manually inputted the actual statistics and then created a difference (actual minus projected) to give me a sense of where I’m “ahead” or “behind.” For example, Valanciunas’ monster double-double last night has me ahead of where I was projected in rebounds but I’m a couple blocks short of where I was projected. I’m not sure whether I’m going to maintain this throughout the week, but it could be helpful since I might allocate starts differently based on how the matchup is going if I’m well ahead/behind in certain categories.
Last, after reviewing projections and whatnot, I used the Plan sheet to guide my entering in my lineups into the Ottoneu platform. It only took 5-10 minutes to get the lineups entered once I knew exactly who I wanted slotted where and when.
So that’s my (work-in-progress) process for figuring out basketball lineups. I suspect that MNF is going to be when I sort out most of my basketball lineup plans, at least for the duration of the football season.
I don’t know to what extent what I’m doing with my offline spreadsheets could be added to the platform for some sort of lineup sandbox since I’m leaning pretty heavily on Rotowire projections, which I assume can’t be integrated into Ottoneu. But maybe the matrix that I described in the first tab, where each column is a lineup slot and each row is a player/date? It could be handy to have that with the schedule view below and then drag-and-drop into the sandbox.
IDK. I feel like basketball is going to require some planning well beyond what you have to do for baseball or football. However, it’s possible/probable that the development of some basic heuristics could mitigate the need for precise planning, so what I’m doing for Week 2 might not be necessary for Week 22.