The changes that you made are a good start, but you're still likely to get crushed by most Boros starts (and Boros is pretty popular right now) and any deck with some amount of creature removal. I would probably start with getting rid of the
Travel Preparations 
. I'm not sure what your intent is to having them there, but they aren't going to be fast enough to turn your mana guys into effective blockers (or into a threat) and if you're able to get one of your big angels out there then you don't need counters. My best guess is that they're there for the interaction with the
Herald of War 
, but I doubt that will come up enough to make what is still only a mediocre combo worthwhile.
Having three
Defy Death 
s also seems a bit much to me, especially once you've gotten rid of the mulches. Without a way to get the creatures into your graveyard you might as well just replace those with creatures themselves. Or more early game plays.
Fiend Hunter 
s can make for a nice way to slow down your opponent. Also,
Tree of Redemption 
is common in sideboards for dealing with fast-starting aggro decks. They can block
Wolfir Silverheart 
while also recovering your life if you've gotten very low. Your deck doesn't have a way to abuse the card though (other than the
Travel Preparations , which isn't powerful enough anyway) and the
Mikaeus, the Lunarch 
s, which are possibly too slow.
It's a little hard to tell if your deck is trying to just go big with
Sigarda, Host of Herons 
and
Avacyn, Angel of Hope 
or if it's trying to put out a lot of smaller creatures and then pump them with
Mikaeus, the Lunarch and
Angel of Jubilation 
. You can try to build the deck with two possible win conditions I suppose.
For your sideboard... I don't think that
Worldslayer 
is really a playable card as it just takes too much time and mana to do anything and then it might not do anything anyway. I also can't imagine a match where you would want to sideboard in 4x
Moonsilver Spear 
s. I guess one or two for a control matchup might work. Really think about which decks are popular out there (maybe check the daily events deck lists from MTGO) and then think about which one your deck will play well against and which it will struggle with then set up your sideboard so that it can help you with the ones where you struggle while still being able to beat other decks after they've sideboarded in against you. If this is to play at your local shop or FNM then do the same thing, but thinking about what decks your friends are likely to play instead of checking the daily events deck lists.
Descendants' Path 
is a pretty iffy card as well I think, although I've never played with it. I'm interested in how it works out for you.
Good luck!
