Maths offers two attack-decay envelopes. It can function in more complex manners with some creative patching. You'll want some ADSR envelopes somewhere as well. ADSR envelopes come in two general flavors: linear and exponential. Some ADSR units can do both. Intelligel makes a nice two EG unit for linear. Tip Top makes the Z4000 NS EG that can do both linear and exponential... and also gives you CV input to control each stage externally. You can find basic compact LFOs, like the Batumi with Poti expander with four LFOs available. I'd also recommend an Ornaments & Crime module for functions like quantizing and a basic sequencer. Sequencers do more than just play notes if you use them correctly. Think of it as a modulation source as well.