Round out team or is it okay?

What heroes do you have?

I can copy-paste you this, it's a list of useable 4* budget heroes. This excludes heroes that are only available as 5*, since those are usually still the better budget options. hope it helps:

Hana - really strong attack and speed. Life and Death is a great skill and Armorslayer is fine for budget use. Watch out for counters. Luna or Glimmer are nice skills to learn her.
Ogma - Great stats, good weapon especially while default Defiant Atk is active. Has a decent special as well. Fill in the blanks with what you can miss.
Tiki (Adult) - Good tank and gets Lightning Breath+, Bonfire and Defiant Atk which she can use. Add in Quick Riposte 2 and a useable Assist and she’s good to go without much work.
Tharja - Comes with a good weapon, great stats, Darting Blow to double and Vengeance as special. Getting her Ardent Sacrifice and Desperation 2 will make her great, but she’ll do without.
Effie - Major attack stat and comes with Death Blow and Wary Fighter as well as highly useable Silver Lance. Needs nothing else to be good, but can become better with inheritance.
Cordelia - great attack and speed. Comes with Brave Lance and Triangle Adept, so she’ll be a major force against red units. Can become godlike with inheritance, but is cheap to use as well.
Catria - a defensive flier thanks to default Armored Blow and very decent def stat. Comes with Killer Lance and Luna to good deal damage too.
Shanna - pretty much the same as Catria, except with Iceberg & Resistance instead of high defenses. Her default desperation & threaten makes her more offensive. Learn her Ardent Sacrifice and she’ll be a really cheap force.
Nowi - while she only has Lightning Breath and threaten res to begin with, she’s very potent with just those two skills. Give her a good special and she’s fit to be used. Fill in the blanks with anything useful. Her defenses make her able to even use Defiant Atk/Spd effectively.
Robin M - Comes with decent stats and a good tome and special to start with. Is a very decent fighter when inheriting imperfect versions of Triangle Adept and any of the breaker skills available to him.
Raven - Great stats and solid default skills. Might benefit from imperfect Desperation and a more offensive special and A-slot skill, but doesn’t need the tweaking to be useful.
Barst - More defensive Raven, with a good assist that only needs an offensive A-slot skill & special to be good. Imperfect Renewal would fit his B-slot and make him durable and strong.
Camilla - Pretty much a flying Barst with great skills to start with. Will lack a bit in the damage department later on.
Nino - Great weapon and stats. Will do good work with an imperfect Fury and any offensive special.
Boey - Defensive mage who comes with all the toys a defensive mage might want. Gronnowl, Ignis, Earth Boost and Renewal. Play him in the center of your team for owl buff and he’s good to go.
Kagero - Poison Dagger and Reprisal are great. Kagero has great stats too. Death and Life 2 will be fine for a budget Kagero. Default daggerbreaker is fine too, but another breaker skill might be used if you lack specific color coverage.
Klein - Brave Bow, Death Blow and Quick Riposte are all great in their own regard. Add in Klein’s very decent stats and he’s the best budget archer you’ll find. Even comes with a usable special, although this might be cheaply improved upon.
Rebecca - Has a great speed stat and comes with Darting Blow & Ardent Sacrifice. While it needs some setting up, this default moveset makes her a good user of Desperation 2, which’ll let her double her Silver Bow for good damage without much investment.
Niles - His default moveset makes him do great damage with his special: Killer Bow, Warding Blow and Iceberg. He fits in pretty well with Catria and Shanna in this way.
Gordin - While a Klein-light, still comes with Brave Bow, +Atk and Vantage as good skills. Has high defenses, so would benefit from a special such as Bonfire.