You are confronting the fundamental dilemma of BIM: how much to model.

Most users develop a sense based in the fee and in whether the design is actually supposed to solve all of the problems or whether implied solutions are adequate. Conventional buildings should need less modeling since you might already have details for most conditions or expect the trade to solve it [or call you to yag on what to do, consuming your drinking time].

If you are going to provide numerous building sections that locate joists and actually solve all of the framing issues, then model the frame. The process will also tell you something useful about design problems.

Modeling the joists as beams is the same effort as making a framing plan, so if that is in your work scope, then modeling joists pays off in other views. For instance, to model the joists and then extract three cross sections saves you the trouble of placing joist symbols three times and will update when the design changes.

There might be framing add-ons that place joists automatically, but they don't necessarily conform to all building codes.