i think that it's competely up to you as to whether you have another baby shower or not. a friend of mine also didn't have one for her first, (she was young) then had her 2nd child 5 years later and had one then. perhaps if you feel abit uncomfortable about having one cos you don't want ppl to feel as though they have to bring gifts (or expensive gifts) perhaps stipulate that on the invites, something along the lines of the baby shower is to welcome the new impending arrival and gifts are not preferred, perhaps instead people could write out in a book their 'pledge' of help after baby is born, eg they could write that they pledge to bring around one meal and one load of dishes done, instead of gifts. this may be more helpful, presuming that you have most of the paraphernalia from you first. maybe a few of you rellies and close friends could all pitch in to help you purchase the higher ticket items that you need?
as for the engagement, again whenever you're ready, especially as having bubs will make it difficult. we waited about 3 months to have our engagement party, while ppl i know have been engaged for 7 months and still not had their party yet or set a date. guest expectations depends on your friends and family. usually ppl bring a house type gift, something practical. if you have things you particulary are after, perhaps drop hints and tell the gossip or organiser of the family, and again those that want to can pitch in.
another idea is instead of having the baby shower b4 bubs is born, maybe combine both the engagement and the welcome baby shower at once, maybe with a bbq and everyone brings a plate to take the load and stress off of you.
hope these help. and congratulations and goodluck with bubs and fiance!!!
SA mum to Ben (10/04) Rianan (7/06) #3 due 14 dec