I've used
Logisim Evolution pretty extensively to simulate a computer using a W65C816 and 74 series ICs. And met with mixed results.
Logisim is amazing as a logic gate simulator and also one of the most intuitive editors I've used in terms of just being able to draw up a circuit. Logisim Evolution takes Logisim (actually Logisim Holy Cross) and adds a lot of missing features, performance and general quality of life improvements. But. Also includes some very verilog related restrictions and introduces some pretty bad bugs*.
I'd recommend Logisim Evolution to start with but it becomes fragile with large circuits. And as barnacle has said it is also missing a lot of the common 74 series ICs.
I've coded up a bunch of them myself (including the 138, 374, 541)
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And they are all
publicly available with an unfortunate caveat. To simulate the W65C816 I had to make a change to the Logisim Evolution source. That pull request was accepted into 3.7.1 but was then overwritten by someone else's bad merge and lost.
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And here is where things get tricky, and why don't recommend Logisim for large projects. It's fundamentally not built for it.
Digital is another option, is more mature in terms of developing (test cases) and is faster. But I could not work out how to write plug-ins for it and could not simulate a 6502 or 65816 in it.
If you want to go the Logisim route PM me and I'll walk you through how to get Logisim Evolution going with the changes I've made. Or, a thought just occurred to me, I may be able to host the executable here.
Going a but off topic, what I ultimately am looking for is something like Logisim that understands voltage levels, propagation delays, has actual working bi-directional ports and can export to KiCad. Of course no such program exists but... it would be great if it did and be pretty much the perfect tool for 6502 development.
* some of which I've fixed.